i find unity gain, when using it as a compressor..
typically, for my amp, that's about 2:30
then, for blend, straight up noon...
and for sustain, straight up noon.
if i want squish, i go to full right on blend, and about 1:30 on sustain.
factory settings inside. (yes, there's a trim pot)
but my favorite way to use it, is VOL max, blend all the way to the left (bypassed) and then it's a Clean Boost.
that, with my lead channel, is a super smooth sound, especially when i'm using a single coil neck sound with a glassy setting on the amp.