i just purchased a 9780 over ebay to use here in the US with at&t. I originally wanted the Rogers one, and now i am being told that i might receive a Bell or Telus unit.
My Telus is branded, and my Telus Storm never lost its branding in almost two years of use. That said, I'm still on Telus, so I'm perfectly alright with that, but bad luck for you.
if the branding is anything like it was on the AT&T Torch you can use the cooper penny to remove it in all of 10 seconds. there is a video in the torch section (use the search to find it) i did it when i had mine and it came off super quick. not sure if the telus one is the same.. i got a bell one.