Alot of the gain on a III is in the power amp, a IIC+ is all pre-amp.. The IIC+ is a smoother gain, so you'll find that comparing settings to get the same tone, you'll run the III at lower treble settings, and lower presence..
You then will lose some gain compared to the IIC+, so the lead drive will be set higher, and you'll need to pull the middle, or R2 knob, to add gain and smoothness. I can get super close to a IIC+ with my blue striper, but it still doesn't get all the way there. But the tone is 99% there... I actually like the III just as much as the IIC+, but it's just not as collectable...
I play the crap out of mine, and it serves me well. I use all 3 channels, and change my settings alot for different songs. I'm not a collector. I'll put my Mark III and thieles against any IIC+ in a tone war, and listeners will never hear the difference......But when a guitarist A B's the 2 amps, they will FEEL the difference, and that's about it...
ax. :twisted: