Not in my case, because I do a lot of conversions on the fly, and also I have a huge group (9 players when everyone is in) so i fudge levels and everything a lot to challenge them properly.
it will be a problem I believe towards the end of the AP, but untso far it works fine.
When I have time, I will do a play report on the Paizo site, but really not enough time for now. If you have any specific questions, ask away though.