Yes I'm using it, and I just did a re-appraisal of it.
I'll state a prejudice toward Meguiar's products. I think it's only fair for others to know where I'm coming from. I have used most other products and I can see how others prefer them; most of them are excellent. I happen to be comfortable with and get outstanding results from Meguiar's.
My initial opinion was that #21 is an excellent product but perhaps not worth the extra cost over other already available products. There are many other worthwhile products that don't require a buy-in of a half gallon; Klasse, 4*UPP, the Poorboys, almost any other Meguiar's product, the Mothers products, and on and on. For #21 to be worth it IMO, either you need to be a professional with the ability to turn a lot of product or you need to decide that you will use #21 exclusively from here on out; a half gallon of #21 will most likely last a home user for the rest of his life. If you have a garage full of detailing products, you need to think long and hard about using them up before buying #21.
That being said, it's absolutely a superior product. The cleaners are a non-issue IMO. They are so slight as to be almost nonexistent, and upon first application the product lays down what seems to be an optimal film density, not needing subsequent applications to ensure maximum effectiveness. Those here have used it can relate, I think; the stuff is more spreadable than anything else I have ever used, spreadable like Klasse SG (with the noted difference that SG is watery and #21 is viscous). I can do my entire Miata with one pad saturation and a couple little refreshers, one at the rear quarter and one at the passenger door; maybe half ounce to an ounce. Wipe off is a breeze, requiring almost no effort whatsoever. The very slight cleaners remove any residual contamination, which creates the greatest opportunity for longevity and durability; films last longer when they aren't covering contaminants. You'd never put this product over top of another one anyhow; in a layering scheme, it would go first.
Appearance is bright, glossy, and reflective, with superior "jetting" and wetness. And it is slick, as in really slick. When you wipe your hand over the paint, it feels like you have glycerine on your fingers.
For me, the greatest characteristic is that sticky stuff washes off with a hose. It doesn't matter what it is: tree sap, pollen, bug guts, bird droppings, or bee excrement (we get a lot of that here); a hose blast blows it all right off.
Recent changes in my employment have changed my driving and detailing habits, and consequently have changed my requirements from my products. The second best characteristic of #21 is that the product maintains its look deeper into the wash maintenance cycle than others I've used. It has lost none of its beading nor slickness nor beauty after 6 washings in the last month. That means I have a bit more time to spend with family.
I'm still in the air as to whether I'm going to buy #21. I have enough other stuff to last a lifetime already. It's tempting, though. For comparison of how I think about it as an economic decision, I'd buy #21 as soon as I'd buy Zaino, and I really like Zaino; I think it's as good as the Z-heads say it is.
If I were to compare #21 to any other product I've tried, I'd say the closest is 4* UPP, mostly because of the slickness. I'd also say that if you already have UPP, use it up before getting #21; the difference isn't so great that you'd notice it more than you'd notice the hole in your wallet that a half gallon of #21 would make. If you're already using Z, there's no need to switch; the results will be essentially similar, and there's no need to switch from one superior product to a different superior product. I'd guess that some others that I haven't tried would also be great; Wolfgang and Blackfire come to mind as products that have been praised by people whose opinions I respect. Klasse has a different look and feel, but it too is a superior product available in smaller sizes at lower cost.
OTOH, if the money isn't an issue, or you don't mind the wastefulness of having more than you'll ever need (that's my real issue), then by all means get #21, it's a superior product, as good as any I've ever used IMO. But keep in mind, the difference between the very best mentioned here and the really good mentioned here was never all that great to begin with.
Tom
