Besides looking perhaps cooler than the rest of the gun, and looking as solid as a rock, what are the advantages to this stock?

From the limited info I've seen on it ( might be the wrong stock... ), it is supposedly 3-5 times stronger than the normal A2 stock, and that's about it.

What is so special about this thing other than asthetics?

No hole in back of stock, plus slightly wider and longer so it distributes recoil forces better.  It also is designed so that it can extend to a preset length instead of having to "count holes" like a normal CAR or M4 stock.  I believe you can mount a picatinny rail on the side to mount spare battery compartments, etc.  and it comes with a sturdy single point sling mount.

And what you already mentioned, GREAT cheekweld and rock solid when locked into position.  It is pricey, but having bought one I honestly believe it was worth the money (and I am a penny pincher at heart!)

It seems to be a bit heavier than a standard solid stock, but that sctually helps shift the balance point of my carbine back, which I prefer.

It should have a bunch of additional add-ons in the near future, too.

Oooohhh. I always thought that this thing was made for style.

But in the fully extended position, there is a small gap between the end of the buffer tube ( I think ) and the butt. Can't crap get bunched up and caught in there ( If I ever manage to get a carbine, I want to USE it, not make it a hangar queen, see? )?

Look here for several reviews of the stock. For what its worth, I believe they are the greatest stock for an AR15 on the market to date. Bar none. There are a few other very good stocks that I like and own, but my favorite gun has all of my favorite gear, and it has a Magpul M93 stock!

Reviews are here;
[url]http://www.ar15.com/forums/topic.html?b=2&f=124&t=140001[/url]

Cheekweld just got better, the Magpul M93[b]A[/b] has just been released!

Check it out [url=http://www.ar15.com/forums/topic.html?b=3&f=12&t=176100]here[/url]