I really don't know why they needed to change much.They addressed the two issues they had with the Protec and completely redesigned it.First issue was it didn't have the Triax pockets and the second was the balance of the reflex riser wasn't as nice as the reflex of the Ultra.The reflexed parts of the Pro to give it balance and added triax pockets.This should be one of,if not the most shootable bow available right now.Oh yeah,it's faster .
I'll let you know how it shoots in about a month.
The Ultratec has already proven itself and as far as the speeds are concerned,I really think the numbers they gave on the Xtec and Ultra were right on last year.It seems that the 05's that are being tested are going above their advertised speeds so I would say they are just being conservative and most will be pleasently surprised.