The big one, not the mini.
I've never liked the channel layout (with Mark-IV, the mode I'd use for leads, falling on the same channel as IIC+ and Extreme, which is the mode I'd be using for rhythms). But, 99% of my distorted lead playing on my Roadster is done on Ch 3 Vintage, my "lead" sound...
I guess I missed when this was posted in December:
Video: John Petrucci ~ Mark V ~ Settings and Tone Tips
I forgot I used to scoop the mids on my Mesa's EQ. Just tried it again after a phase of thick mids. Sounds great for Dream Theater riffing \m/