I am late on this thread but you prolly made the right choice on accident. For your future reference, you really need to have your builder choose your pipes to compliment their style of porting. Rob had his pipes made to compliment the way he ports and sets motors up. That is not to say that Robs pipes won't work good in other situations, but they will compliment his motors best. Other builders have their favorite and what works best for them. Nate Mccoy prefers Shearers, Tim from Titan Seems to like CPI's....
Anyway, hope you like your pipe choice and definately keep us updated on the dyno results. Rob builds a mean motor, you should be real happy.