I just threw on a set of used 205/55R16 MXs. After some F1-style tire warming swerving (not on the road, of course) to get the skin off and warm them up, I had a pretty good romp.
Straight line: either smoke or wheelhop. Harder to launch than the Fuzions, but I think they have a little more grip. I was at 35 psi, so they might hook better at lower pressures.
Braking: With ABS they felt good, and the compound/carcass liked crappy pavement about as well as the smooth stuff. Without ABS threshold braking at low speeds was a chore. Again, they fall of quickly at the limit and keeping it on the edge is tricky. Not R-comp tricky, but tough for a street tire. I'll see how this changes as they get re-broken in.
Trasitions: The big sidewalls are sort of mushy. The Fuzions had a soft sidewall for a sporty tire, and I was hoping for something more Azenis-like here, but I didn't get it. They're not rolling over at 35 psi like the Fuzions, but they are still softer than my springs. But, it's a fairly linear feel, and I think it'll be fun and forgiving.
Steady-state cornering: loads of grip. These tires are tenacious. Not worlds away from the Fuzions, even after they were heat-cycled and worn into oblivion, but the butt-dyno says they're better. They have a very smooth (but short) transition into sliding. The tall sidewalls let me run huge slip angles and change the attidude of the car without getting loose, though. They do not squeal on dry pavement, they just let go and leave thick dark black marks: very much like an r-comp. These will be tougher to drive than the Fuzions, which had a very forgiving "double-hump" slip-angle vs. coeffeicient of friction curve. But, the tall sidewalls will make it happen slower. I could not induce excessive oversteer on a ~30 mph skidpad, even with the inside rear lifting. I think that this means they like camber. The fronts really felt over-cooked. I'll try again with the race setup of ~3* camber up front and see if the rear will get loose. At higher speeds (~50-60mph) it got wiggly when lifting at the limit, but nothing dramatic. Again, camber should improve rotation.
Real-life stuff: These are DD tires. They are very loud. They hum, and they get louder as they get warmer and grippier. They tramline a bit, but I think they are better than the Fuzions. I have yet to try them in the wet. Ride: well, they're a lot stiffer than my 14" winter tires. But they're still much softer than my springs, so it's tough to tell what they'd be like on a softer car. Ride quality is always crap in my car, even on pillow-soft tires.
In about a month I should be able to try them on the course, and we'll see how that goes.
