I sometimes visit Toronto for work, and when I do, my visits are short and I'm downtown. So, I'm mostly limited to downtown possibilities for a massage. I've tried (and reviewed here on massageplanet.net): Kawaii, Tui-Na, Executive Massage Spa, and AHC.
I've also tried (but not reviewed): Spring Green Massage (somewhat tired but clean room, below-average shower, cute MPA) and 59 Elm (average facilities, below average shower with very low ceiling, friendly staff). Both places charged standard rates, and I got the sense more could be available with repeat visits.
5 out of the 6 I've listed are just a few minutes walk from Dundas Square or Eaton Centre, so there are definitely possibilities downtown. (Though I wouldn't recommend Tui-Na.)
The 6th, AHC, is a quick train ride from downtown. I've visited a few times now, and each time has been fantastic. My best session ever was at AHC. I think it is totally worth the 10-15 minute travel time. Just my two cents ...