Anything that is class compliant is going to work, imo better than specialized drivers. I love this setup I got going here... I managed to make the Model 12 the main audio interface since working out the details. The other audio interface is a Roland TD-27 drum module. With ALSA, I'm able to load it as the secondary audio interface, and use JACK to plug in the 28 tracks from the TD-27 into Reaper. That's 28 tracks for drums (2 stereo overhead, 2 stereo room, then mono/stereo for each drum module). I'm using 12 of those tracks, but I don't have to go through the Model 12 at all, leaving that interface open for other instruments. Hello to live recording a total of 20 tracks!
I don't really care about using the Model 12 for a DAW control, to be honest. So, I haven't really looked into whether or not that works.
There is limitation in the amount of VSTs available, but there's so many good VSTs available for Linux that it doesn't matter. If you have some outboard gear, that always helps. Airwindows alone, you could get a lot of really good VSTs to work with.
I've used WINE on some VSTs, but WINE isn't all that great. The biggest problem I came across is finding decent synth VSTs, but it really depends on what you're looking for. I bought an Arturia Keylab for the purpose of using Analog V and Piano V, and they just don't work well in WINE. I have an old Macbook powerful enough to be a synth beast, so I plug that strait into channel 9/10 in the Tascam.
I love the Model 12 for practice too: I have the TD27 stereo master out in channel 7/8, guitar and bass amps are plugged into IRs strait into the board, plus 2 vocals. Everything is mixed live on the board to the sub for headphones. I don't even turn the computer on, if we got a good idea I can just record on the SD card. We're jamming our asses off at home in my basement, all the while my wife and kids enjoy a quiet life upstairs.
My linux machines have SD card ports, so if anything is good on the board, I can import into Reaper, either record direct or move the files over. Incredibly versatile. I had my hesitancy at first using Linux, but now I don't think I would do it any other way.