There hasn't been any serious connection/cell issues that I've come across yet. The service definitely drops off inside our house if I'm holding it a certain way - but the free case that's coming from Apple should alleviate that. I've had great service just about everywhere else. And since Telus is using the same 3G network that Sasktel is building, the service should only improve as time goes on.
As Carlos said, the main drawback to Telus so far seems to be the fact that you have to have a 716-xxxx number, which sounds odd in Saskatchewan.