I have used it and talked about it recently in the asethetics forum.
I first used it on my Jeep GC on Easter w/n. Process was:
Wash w/ NXT soap
Meguiars clay bar
Meguiars #80 applied w/ PC
Meguiars #21 applied w/ PC
Meguiars ASD on tires and trim
Here are some pics of the finished product:
(Ignore the dust speckles in the last pic, the Jeep sat overnite before taking the pics).
I applied a second coat a few weeks later (no pics) and haven't waxed it since. The water still beads up like crazy, even when the Jeep is dirty.
For some good reviews and more pics, check out the #21 Forum on Meguiars On-Line:
MOL As I mentioned in another post, this product goes on very thin and I've used it 3 times and hardly put a dent in my 12 oz sampler. I can't imagine how long the 64 oz bottle would last!