I use a Maxon OD-808 for the light overdrive tones, a Klon for the bigger overdrive tones, and I use a Treble booster clone (w/ darker tone mod) for my marshall sounds, and sometimes I use all three for screaming distorion!!! For the more blues related stuff, I just use the Klon and OD-808.
TIM is set for light overdrive. AC boost is set for medium overdrive. TIM with the internal boost engaged into the AC boost for the heavier stuff.
The TIM itself is set for unity volume with my clean amp.
The AC boost is set for a volume slightly below unity. If I engage the AC by itself, it's the perfect volume for doing background fills and runs just underneath the vocals. If I need more of that sound I can roll up the guitar volume a touch.
When I run the TIM (with internal boost engaged) into the AC, I'm just slightly above unity volume and get a great, thick rhythm and lead tone.
I actually am really liking two combos right now:
MJM Blues Devil and Tim AND MJM Blues Devil and the Keeley Java Boost.
And just to add something......that MJM just gets better everytime I play it.
I'm geeting some great results using an LP and running my MJM Blues Devil into a Tonebone Classic. The Tonebone is a great pedal by itself....add the Blues Devil and the combo provides just the right amount of spine tingling clarity; tons of sustain and note bloom and pushes it over the top.