Just wanted to share some impressions now that I've had the Mad Professor Supreme for about a week... It's really impressed me so much! It's my first Mad Professor pedal and therefore I have no basis of comparison against any of their other designs. The 'A' side (left) is based on the MP Royal Blue and the 'B' side (right) is based on the MP Simble (although their promotional material doesn't call that out implicitly). First off, I find the build quality of the pedal to be top-notch. It seems sturdy and I have no concerns about its longevity. I think it's also quite a looker - I love the color which reminds me of Fender's Ice Blue Metallic. I really like how they've marketed this pedal - use the A side for your neck pickup and the B side for your bridge pickup. Maybe I'm alone on this, but I've never approached a double OD pedal in this manner. It seems simple enough, of course, but it really changed my approach for dialing the Supreme in. First off, it was interesting to try the pedal with all eight knobs set to noon. You could hear that each side has its own unique and distinct voice. Even with extreme EQ tweaking, I couldn't make one side sound like the other - for me, this is a positive. I like that the two sides are voiced differently. It was interesting to try both the A & B sides with the neck, middle, and bridge positions on my Telecaster. With everything at noon, the A side sounded best with my neck pickup (and in the middle position) and the B side sounded best with my bridge pickup. This was a bit of a revelation for me! I guess it made me think that, with every other OD that I've tried, I just try to dial it in to sound good with my set-up...but that forces me to make compromises. Some ODs sound great regardless of which pickup you're using, but I believe that this approach of dialing in each side for a particular pickup allowed me to really optimize that circuit to achieve the best possible tones that it has to offer. With all of that being said, I began to dial in the A side to really bring out the best from my Tele neck pickup - Vol & Gain at 10 o'clock, with some bass cut and some treble boost. Sounds fantastic! Then I dialed in the B side to make my Tele bridge pickup shine - Vol at 10 o'clock, Gain at 2 o'clock, with some bass boost and treble cut. It was really interesting to then try my neck pickup through the B side and my bridge pickup through the A side...I really didn't care for it. Again though, no wonder some of my other ODs sound best with only one pickup position. And if they sound okay in all positions, then I've probably compromised too much and I'm missing out a bit. The switching options for this pedal are really cool! With the toggle switch set to the right - the left foot switch turns the A/left side on & off and the right foot switch turns the B/right side on & off. In this mode, both sides can be on at the same time (B into A)...personally, I didn't love the stacked sound all that much. Alternatively, you can have the toggle switch set to the left - the right foot switch acts like a global on/off for the unit and the left foot switch toggles between the two sides. There is no ability to stack or have both engaged simultaneously in this mode. Strictly from a utility perspective, I'd say that the MP Supreme is the most versatile double overdrive that I've tried. I've also owned all of the following double ODs (or OD+Boost) - CopperSound Foxcatcher / JHS Double Barrel V3 / Lovepedal Amp 11 (Big Box) / SolidGoldFX Zeta DLX. I understand that it's not fair to compare all of them because they're all different styles...but strictly in terms of sonic versatility, I'd give the MP Supreme top marks!