I just played a stock Mesa Dual Rec Multi-watt next to my Voodoo Platinum modded Dual Rec Multi-watt. Yes, the fizz in the upper mids is gone. It tightens up the bottom end to make it more punchy. The amp is super articulate, and allows you to roll off your volume on your guitar a LOT better, and it cleans up REALLY REALLY well. It really makes the Dual Rec much more usable across all the tones (MOdern, Vintage, Raw). The amp is by far the MOST versatile amp I've ever played. It goes from Metal, to hard rock, to rock, to even a bit country on Clean channel. It can go from Eric Johnson style cleans, to chicken picken really well. The amp is totally a new animal, with the lineage of a Dual Rec, but just a better overall tone, EQ stack, and setup. It's definitely a must have mod in my book for the Dual Rec.