I have a 20' Schiada. I wanted a 21 but found a good deal on this one. It even fits in my garage much better than the 21 would have. I owned to very nice flatbottoms before this boat. My last flat was blown, injected and ran 8.20 @ 128mph. I love my Schiada so much. It handles so well and just eats the chop. The 21' from what I hear is even better. As far as acceleration goes, I'm pretty jadded from my last boat. But this one is pretty good. Wait until it gets nice and sloppy out and then start picking on the jets. Dock manners, just about like a mid enegine ski boat. They don't steer real well in reveres but it's no big deal at all. I think it gets around the docks pretty well. Sundeck, I have an exposed engine but the non-skid deck is huge! Like an aircraft landing strip. My wife loves it. Speed, mine came with a twin turbo 461. It ran pretty good but i never GPSed it. It's getting a new 573 turbo deal now so it should be able to keep up with most of the Jones's. (hee hee)
All and all, if I hit the lotto I might (would) buy a big off-shore boat. But I would keep this one for my lake steed. Get it, you'll love it. The only down side is that it will cost twice as much as a nice 21' jet boat. Worth every penny!!