If you are wary of either one, go to cellclients.com and take over an existing contract. You can get a lot of perks that way and maybe even cash to buy an Iphone5.
In my experience I hated Rogers but never tried Telus. If I were getting a phone contract again, I would either go with no contract ie Wind or Koodoo or take over someone else's contract for a shorter time like on cellclients. Once these guys lock you into a contract it is hard to get out of.