Is anybody seeing numbers like this using ASIO with USB2?
 

 
I have a 10 year old Firewire 410 that still works well on my newest desktop with an add-on firewire card.  My old laptop had a firewire port, but my new laptop only has USB2 & USB3.
 
So if I was going to get a USB2 audio interface, is there any chance could I get the same buffer setting to work on the laptop?

It will depend on the audio interface/driver manufacturer, and possibly on the specific USB adapter. RME and some others have extremely good USB latency performance, but many do not. Many USB interfaces also have a lot of non-buffer-related latency, some of which may not be reported. In your example, there is 314 - 2 x 64 = 186 samples of hardware/firmware latency (FW interface and A/D/A conversion) being reported in addition to the buffer latency. Some USB interfaces will do better than that, and some worse. But you'd have to measure the acutal RTL using comething like the free CEntrance latency tester to know whether the reported RTL is accurate.
 
By way of comparison, at 64 samples, the reported RTL on my MOTU (PCIe) interface is 173 samples, and the actual, measured RTL is actually 2 samples lower than that (with most interfaces, it will be higher).
 
EDIT: I should point out, too, that 'mixing latency' is technically only the Output side, but most users are more concerned with monitoring latency, which is the total RTL.

What's your budget?
 
RME and MOTU are the usual suggestions for low latency on USB2. 
 
On the less expensive end, you should check out the second generation Focusrite Scarlett Series (The first generation are still being sold, but the latencies are just so-so. You need to look for 2nd gen).  The lower, bus-power models of the series are already available, but the top three models (6i6, 18i8, and 18i20) are due for release later this month or early next.
 
There's also the Zoom UAC-2/8 interfaces. You will need USB 3 for these (I believe they work with USB2, but you won't get the low latencies).

My MOTU 896mk3 Hybrid (USB 2.0) with a 64 sample setting gets Input 2.7msec, Output 3.3msec total roundtrip 6.1ms.  
 
I also have a Roland Octa-Capture (USB 2.0) and it is Input 4.8msec, Output 2.8ms, Total roundtrip 7.6ms. 
 
This is much better than I did with a Focusrite Saffire Pro 40 and Firewire.  Best I could do (reliably) was Input 11.4 ms (don't remember output or total).
 
The MOTU gets the same latency on both Windows 10 and Windows 7 (I have a dual boot system) with the same hardware.  However, the Octa-Capture is slightly better on Win 10.  On Win 7 I get Input 6.2 msec (reliably).
 
I tried a Presonus Studio 192, which is USB 3.0 interface and at 64 samples it was about the same as the Octa-Capture.  I only had it two days.  The first day it worked OK, the second day it developed a problem (would not power off) and was sent back and replaced with the MOTU (both the same price at B&H).
 

fireberd
I tried a Presonus Studio 192, which is USB 3.0 interface and at 64 samples it was about the same as the Octa-Capture.
 

 
I looked hard at the Presonus interfaces when I was last shopping, but voted them off the island because of the unusually high latency at any given buffer size that users were reporting.

brundlefly
It will depend on the audio interface/driver manufacturer, and possibly on the specific USB adapter. RME and some others have extremely good USB latency performance, but many do not. Many USB interfaces also have a lot of non-buffer-related latency, some of which may not be reported.

 
I expected that might be the case.  It sounds like there is a wide, rather than narrow, range of latencies among different USB interfaces.   
 
That is one reason I originally went with FireWire, due to the technical differences in how the bus types were handled by the PC.  FireWire 400 supports speeds of up to 400Mbps, while USB 2.0 operates at 480Mbps.  That's enough bandwidth to record and playback more tracks than I will ever need. But I was more concerned about the "other" types of latency occurring with the USB bus. FireWire operations didn’t require as much work from the host system’s CPU; and FireWire could transfer data in both directions simultaneously (“full-duplex”) where USB 2.0 using a polling mechanism arbitrated by the host can only send or receive data (Half duplex).
 
Apple stopped including FireWire due to cost and other factors, and USB2.0 "is good enough" for most uses, except for applications that justify high-end PCIe and Thunderbolt variants.
 

brundlefly
In your example, there is 314 - 2 x 64 = 186 samples of hardware/firmware latency (FW interface and A/D/A conversion) being reported in addition to the buffer latency. Some USB interfaces will do better than that, and some worse. But you'd have to measure the acutal RTL using comething like the free CEntrance latency tester to know whether the reported RTL is accurate.

 
I was hoping here that some folks could say "Hey, I'm getting this RTL [x.y msec] with [insert-interface]" just to get a rough idea of what to expect.  I realize that my mileage may vary.
 

brundlefly
EDIT: I should point out, too, that 'mixing latency' is technically only the Output side, but most users are more concerned with monitoring latency, which is the total RTL.

It would be nice to be able to take my laptop on the road and maybe play virtual instruments ('mixing latency'), or record a buddy's guitar with some effects in the box ('monitoring latency').  So both factors are important to me. 
 
Just for reference, the laptop is: Intel Core i5-4210U, 4GB RAM, 500GB HDD, Windows 8.1(x64).  Don't judge ... it was not bought with audio in mind. It serves as a portable office.  I already have a DAW desktop PC :-)

 
Thanks for the feedback!
 

Presonus has a self setting function that is supposed to set the optimum latency based on the PC system.  When I first installed it and it auto adjusted,  the latency was very high - about 20 ms input and same output with 1024 samples.  But manually setting it to 64 samples brought it down to a useable level (as I previously mentioned about what I posted for the Octa-Capture).
 
 
 
 
 

Motu, RME or.....
 
Those new Zoom USB3 interfaces have astoundingly low AND usuable RTLs! I'm about to order one myself...
 
R

I have just moved from Firewire to USB.
 
I am getting these figures with my new Soundcraft 12MTK
 

JonD
What's your budget?
 
RME and MOTU are the usual suggestions for low latency on USB2. 
 
On the less expensive end, you should check out the second generation Focusrite Scarlett Series (The first generation are still being sold, but the latencies are just so-so. You need to look for 2nd gen).  The lower, bus-power models of the series are already available, but the top three models (6i6, 18i8, and 18i20) are due for release later this month or early next.
 
There's also the Zoom UAC-2/8 interfaces. You will need USB 3 for these (I believe they work with USB2, but you won't get the low latencies).

 
Looking for something portable to toss in the laptop bag for occasional mobile use.

As far as the budget and needs go, I have looked at the Focusrite 2i2 & 4i4. They seem to be nice portable units for the price, with good reviews. I have heard that the 2nd gen likely resolved the issue with hot guitar inputs on the pre-amps.
 
Also looked at the Tascam US-2x2 & 4x4, seem well designed and built, a good value, but have seen a few reviews that mentioned they're not the best in the latency dept.
 
The NI Komplete looks interesting, and is probably near the top of my budget. 
 
I really like the MOTU Audio Express with both FireWire & USB2 connections.  It's a bit above my budget for this purpose, but definitely top of the list as a replacement for my M-Audio FW410 on the main PC if it ever quits on me :-D
 
And that Zoom looks awesome! But it may be overkill for my needs, unless I havet a sudden GAS attack, LOL :-D
 
Edit: I just noticed a smaller Zoom USB3 unit available (2 in/2 out); Zoom UAC-2 Two-Channel USB 3.0 SuperSpeed Audio Interface for Mac and PC. Hmmmmm ... I do have USB3 available on both PC and laptop.
 
Plus another improvement with USB is that USB3 is now full duplex!