It isn't just the SIM card that controls the access. It's like a custom setting that goes in at an OS level. I had a nice Android phone I brought to Telus unlocked from elsewhere. It would see the #TelusDirect network but could never connect even with the Telus SIM card present and full access to everything else. Tech support had no idea how to fix it. Both the iPhone and S6, which I got from Telus, connected instantly with no issues.