i just got one so i'm no expert...but here's my experience so far.
you definitely can't use for everything without sampling parts.(enough

)
it seems to be able to handle 2 full on patches and a simpler one.
Trying to use all four multi parts goes like this for me.
full on synths in parts 1-2
two simple drums in 3-4(yeah i need to get a sampler going in cubase

)
synth one cuts out a few seconds into a pad
......not that i should be using the virus for drums.
if you have a real studio...or just good sampling skills
you should be able to use 2 full on and a simple patch.
on that note, are there any good vst samplers for nu-breaks/morning-psy? NI battery?
As far as the snow not having many knobs, the plug-in is really easy to work with as far as routing cc => parameters for controlling it with whatever you want....not that i didn't wish i had easy access.
i don't think you can run out of voices using 2 maxed patches...how do you use your TI?