So have a Samsung Galaxy s3 mini, have the apn set correctly and am able to use everything. Problem is the EDGE speed varries from 30kbps -190 kbps. If I use the simcard in my old test Samsung Galaxys it gets speeds in the 1000kbps range.
The phone gets speeds in the 8000kbps range when it is using HSdpa but it rarely seleselects that mode.
Rogers isn't limiting the EDGE network. EDGE is the slowest data network on Rogers. It verys on which location you are in and it varies on the phone you have. Also remember, some phones still use EDGE live.
Every single phone is different. Take a look at the iPhone 4 and 4S for instanse. Botth devices run on the same network BUT one is slower then the other one. It depends on where the anntena is and where the location you are in. It could be many things to do with it. I doubt Rogers sits there and slows down new phones...