USB Vs. PCI Vs. Firefire Interfaces

What are people's opinions on USB interfaces vs. PCI or firewire?

I have a 2496 which I'm considering useless compared to other cards I have used recently and I'm looking into the Roland Octa Capture but I've read a lot of conflicting opinions on the stability and latency of USB interfaces.

If anyone has a USB interface (or better yet, the Octa Capture) what's your stability like?  And what's your latency (input or roundtrip)?

Thanks for your help!
dRolan.

Thanks for the advice. 
That being the case.... has anyone here used the Octacapture in conjunction with X1? 
If so, what are your experiences?!

My opinion....

PCIe>Firewire>USB

USB is CPU dependent, way more so than Firewire and  PCIe. USB also tends to add to your DPC latency.
Firewire has dedicated controllers on either end of the cable, but the device is still a layer removed from the Chipset and CPU.
PCIe is the closest to the CPU you can get.

Watch this page, they will have a latency shootout posted eventually:http://www.dawbench.com/

vs pci-e also (which has increased bandwidth)

regardless any "card" is as good as it's drivers and in some cases that's the bit that lets the card down.

Thanks for the help guys.

Ultimate question though is what do you all think of the OctaCapture?!  For the money, do you think I'd be better off going for an internal PCI-e card or Firewire box from someone like RME? They seem to have a fairly good rep...

My experience:

1212m PCI - Very stable.
FA-66 FW Interface - Very Stable.
EMU 0404 USB - Many problems with clicks, pops and latency. Admittedly these problems reared their ugly heads before I did the suggested DAW tweaks not to mention my old Vista PC was connected to the internet.

I have no user experience with the Octa-Capture but the features and specs look good to me. It's hard to say what interface will work and what won't work as the differences can be quite different from one machine to the next. RME from what I've heard and read has a great reputation for solid driver's and performance.

I like PCIe but the problem is none of the currentcards cover all of my needs completely.. RME has got it pretty close if only the had  fx in total mix, then i would be all over it...

PCIe>Firewire>USB

 
In the not too distant past, I would have agreed with this
 
That said, the latest generation USB-2.0 units easily compete with the best PCIe units.
ie:  I can run the RME Babyface at a 48-sample ASIO buffer size (4.3ms total round-trip latency @ 44.1k) while sustaining subtantial loads glitch-free.  I posted a (horrible quality) video showing this a few days back.
That's better than what many PCI/e units can achieve.
I've you've not actually seen a USB 2.0 unit do this... I can understand your skepticism. 
I didn't believe it until I actually experienced it.
 
Much more important than PCIe vs. Firewire vs. USB is the specific choice you make.
 
With PCI/e, most units deliver low round-trip latency... and perform well.
With Firewire and USB, you have to be more careful with your choice (if low round-trip latency is important).
If you go Firewire, using a quality TI chipset Firewire controller goes a long way toward ensuring rock-solid top performance.
 
If you go USB 2.0... stick with RME or the FastTrack Ultra/8R
If you go Firewire... stick with RME, MOTU, or Steinberg

whoops again.

Ok people here is the low down.  I am unsure about PCI express in terms of latency but USB interfaces are quicker in terms of latency than firewire. 

As for the notion of one interface being better than the other at the mid-range mark there is no difference.  I have recently found out that Motu, M-Audio, Pro-Tools and RME all use the same brand converters (so whats in a name).  The only difference in mid-range interfaces are the pre-amps and the clock.

I am happy with my motu ultra-lite, I have used the firestudio project from presonus, the drivers and the virtual mixer are crap (or at least they were when I last used it) so stay away (although their eureka pre-amp is quite nice).  Finally stay clear of the lexicon stuff US42s and the like, although the latency of this device is by far the best I have ever experience, I was able to use the guitar rig 4 and I felt no discernible latency.  The pre amps on the thing are rubbish and because it has no line in's it was a big waste of time.

Remember this my brothers and sisters, the equipment we have now eclipses anything and everything that was used to record the greatest recordings in history and this includes the cheap pre-amps included on most mid-range interfaces.

Recording is like painting and everything has a flavor and or a colour, it's not the equipment but how you use it.

The democratization of the music industry has made the OP post redundant.  It's no longer about the best interface, the best pre-amp or the like.  Every piece of digital technology and even recording technology has it's pros and con's.  The presonus stuff has some of the best dynamic range in terms of converters for the price but is almost unusable on certain P.C's.  The lexicon u42s is great as a live interface if you are going to use it to play guitar and use it in conjunction with guitar rig.  The  motu stuff is like a swiss army knife but if you believe some of the information available it also has the worst clock.

Use this information as you will.

Dr.Hash
www.aaudiomystiks.com 

dr.hashmk3

 .... I have used the firestudio project from presonus, the drivers and the virtual mixer are crap (or at least they were when I last used it) so stay away....

... The presonus stuff has some of the best dynamic range in terms of converters for the price but is almost unusable on certain P.C's.  T
Dr.Hash
www.aaudiomystiks.com 

I guess I should be leery of the fact that my Presonus FS Mobile is rock-solid on 3 different system (all Windows: XP and Vista), since you say they're unusable on PCs.  I'm on Vista 64 too, so there's another impossibility: according to a ton of ex-Vista users, Vista is crap and unusable as well...

When will "ex- users" realize that over time, things can/do improve?  Especially since those users have moved on, so never benefited - how would they know?  Vista got much better after SP1-- even more so after SP2, and drivers were finalized.  For the vast majority of users, Presonus Firestudio are now quite stable on PC (They weren't in the beginning).

That said, you are dead on about the dynamic range for the Presonus FS series.  I'd put my FS Mobile mic pres/converters head to head with any of the so-called high-end interfaces, and for $300, it's easily the best deal on the interface market.

Thank you all for your input -- a lot of really good stuff that you have all said that definitely helps.

However, I wasn't really talking about the difference in pre-amp quality between price ranges, my problem is merely stability with larger projects and the question I keep asking myself is: is it my sound card, my system or Sonar?

I run Win7 x64, 4gb RAM, M-Audio 2496 and Sonar X1 PE.

I run stabily at 1.5ms latency until my projects get a little bigger at which point I need to increase my latency to the extreme but I can still get pops and clicks on playback.

Pre-amp quality and internal clocks aside, what do you good people recommend?

dRolan


Thanks for the advice. 
That being the case.... has anyone here used the Octacapture in conjunction with X1? 
If so, what are your experiences?!

We were able to use the Octa-Capture at NAMM with pretty hefty projects on Win7 at 48 samples reliably.

Jim Roseberry
while sustaining subtantial loads

Heh heh, you said "loads"

Thanks for all your input everyone! I think I will go for the Octa Capture...

Now to gather some money....

eek...