Cool -

I hope to start installing the hardware upgrades when I get some time back home in a few weeks, and really look forward to getting the 18i20 online. Appreciate all your feedback -

Thanks!

I am speaking from owning Scarlett 18i20 Gen 2 myself. It is very fine interface. Here is some of the actual changes between Gen 1 and Gen 2 from their website.
 
The second generation Scarlett range is packed full of upgrades. New super-low latency* will bring confidence to your performance, letting you record and monitor with software effects in real time.
 
New metal volume controls and a sleeker red metal chassis underscore its improved industrial design, built to go anywhere. Scarlett USB audio interfaces also now operate at sample rates all the way up to 192kHz, and the input channels have evolved too.
 
The latest Scarlett mic preamp features a more even gain structure, so you can accurately set your levels, and the instrument input has also been completely redesigned so it can handle seriously hot pickups for recording electric guitar.
 
So there you have the essential things from Gen 1 to Gen 2 are:
 
Latency
Gain changes and improved instrument input design
Sample rate up to 192 kHz which is handy
Improved hardware design
 
The difference between Gen 1 and Gen 2 would be quite subtle I would imagine.  A bigger difference will be had listening to their thunderbolt line such as Clarett. Here the Mic pres are better and the latency is breathtaking like 2 mS and under when setup correctly on thunderbolt on a Mac system.  Playing virtual instruments with this is amazing.  Focusrite control is also a great program to use.  I am lucky in that I can run Studio One on a Mac as well.  Thunderbolt on Windows can be achieved with care.  Not quite as easy as connecting it to a Mac. 
 
You can look into other lines such as RME.  All the RME stuff is excellent.  They also achieve excellent latency coupled with a quality sound.  RME TotalMix is also great.
 
The hottest thing now though is Presonus Quantum.  It has excellent features, sounds excellent and has the lowest latency right now achieved anywhere.  It has deeper level of integration as well with Studio One software. 
 
The fast response is not only useful playing virtual instruments.  It can monitor things in recording and live use. Buses can be setup for PA and monitor mixes and all used in the recording stages. Complex routing can be achieved. 
 
I think there are some excellent interfaces that you don't necessarily have to switch to Mac for though.  And stay on Windows.  Interfaces working over the PCI buss is a good place to start.  And USB 3 for that matter.
 
Getting back to the Scarlett, having said all that I am finding it sounds very nice, has excellent latency anyway for virtual instruments, and for live software monitoring. So you spend nothing and have a fine setup. Or a slight upgrade into Gen 2, a higher upgrade into Clarett or higher end RME products.

Appreciate the comparison - thanks!

The last few days, I'm getting a bad case of clicks from my 2nd generation 18i20.  So what do I know?
 

Not sure what is going on there Matt. It must be at your end though because it is pretty faultless with me here on Studio One on both Mac and Windows.
 
To the OP check this out. You might find this interesting:
 
https://www.youtube.com/watch?v=5zhXijvtkNc
 
Not much around that can come close to this.  Except the computer won't be cheap though. I built one on their website and it came to $7000! I have emailed them and asked them for the specs. But it does show off Quantum in a good light.

I had the  first gen 18i8 which worked fine under Windows 10, but when I saw a really good price for the second gen (came with a whole bunch of audio and MIDI cables at a good discount) I decided to take a chance. 
 
I had read a lot about many problems people were having with the second-gen Scartlett, mainly around the issues of drop outs and pops. but I decided to take a chance anyway. 
 
I did, and discovered I was having the same problems. Playback of Sonar files would hiccup. ARturia soft keyboards dropped out as well. I tweaked the system mercilessly to turn as many system-hoggin resources as possible, but it wouldn't stop it. 
 
But since my PC is around 4-5 years old (I COre-7 second gen with 8gig RAM and a single hard disk), I decided to splurge on a new PC--I Core-7 gen 7 with 16gig, a 256SSD and 1 TB hard disk. I've spent the last week or so moving everything over and reinstalling Sonar and various plugs ins.
 
So far, without doing extensive System tweaking, the second gen Scarlett is now performing flawlessly when I play back older Sonar files, even with audio plugs. Next step is to see how my Arturia keyboards work with it. 

rivers88

bdickens
I have that same interface (gen 1) and it works just fine under Win10.

Byron, which drivers are you sing with your 18i20?
Guess it can't hurt to take it for a spin before I commit to an upgrade. 
 
Thanks!

Whatever the W10 drivers are tbat they had a couple of years ago when I got the thing.

Thanks!

Randy