I got impatient waiting for the new Blade 300 X and had a few extra bucks so since it was just sitting there in the LHS and looked lonely I bought the Blade 450 X too.
Wow! You're in for a treat if you're waiting for the 300 X and it's anywhere close to as good as the 450 X! I am very impressed with it (but I'm not as particular about servos and such as some are). The BeastX seems to work great!
Here's a video of a brief maiden hover and a few pitch pumps. The 450 X sounds great and is amazingly stable. It feels like a giant mCP X to me. It will be interesting to compare it with the 300 X when it is finally released.