This game is an Xzibit joke waiting to be made. Although I can't vouch for the Castlevania aspects, not playing one since 2, there sure is a lot of Metroid in it. There's a little Uncharted in it also, as the Nathan Drake resembling main character is voiced by the same guy that did Nate in Uncharted. He's enough Nate that I don't remember his actual name in game.
My 360 is now cabled and has been powered on in the first time since beating Fable 2 in late 2008. I really struggled with the decision to let the power brick out of its wooden prison and let the 360 roar to life again. However, the draw of a Metroidesque sidescrolling adventure, getting good word of mouth and available for cheap, was irresistible. A demo was available, which allowed me to possibly not waste $15 if for some reason I'm the 5% that hates the universally loved game (see Braid).
Perhaps, the best praise for a demo can be that it leaves you wanting more.