Power Difference 450 vs. 525XC

I am not overly familiar with KTM dirt bikes so I am wondering what the power difference (positive or negative) is going to be between the 450XC and the 525XC version? I am strongly considering getting one of the new KTM's but don't necessarily want to immediately put myself into another racing class above 450cc ... any opinions or experience with either engine? Thanks.

I talked to John Hinz at Ktm today and asked him the same question.He said there is only a 4 hp difference between the 525 and 450.Not quite as violent on the bottom but a shrieking top end.