I may be wrong about this but usually with a BB you have a data package and at the current prices an unlimited data package is relatively unexpensive. My point being why use wifi if you have unlimited usage. I believe edge is edge so it will not be any faster with wifi. I am a gps user and absolutely love the convenience. My vote is for the 8310 and like you mentioned it is covered by warranty. You never know with electronics. Good luck which ever way you go.