Pick the GPS. I always found wifi on a mobile phone to be useless. I had a BB before, and used the slow edge browser when I absolutely had to. I thought the world would be better when I had the iPhone with wifi. Even with the big screen, the better interface, I was always wishing I had a computer nearby. Its nice if you HAVE to get on the internet without a computer around. Thing is, when I have wifi, I have a computer around (most of the time). If Im at an airport with wifi, I have my PC. At home I have my PC, in the office I have my PC, why would I be on the damned phone surfing? Even though my car has GPS, I dont always have GPS. Rental cars, friends cars, etc. Its something nice to have. thats why I picked the 8310 over the 8820.