Hi,
the Ape has a very bad reputation, which is particularly justified. Before You decide to use it, read the Ape forum by AF1Racing to see, what will or can happen.
Also new engines bought in the last two years come directly from the Aprilia plant with wron assembled oil seals, metal flakes in the cases due to careless cleaning and forgotten Loctite on some important bolts.
If You have all the the assembling problems by Aprilia fixed and overwork some parts it is a really nice and realiable engine. But this may take some years...
We use it since 2009 and hope to have all the teething troubles fixed. One year ago I would have said, that we have all fixed, but the Ape is always good for something new ;-)