My personal preference is for S&Ws with the traditional barrel contours i.e. without the full underlug for the following reasons:
-Looks
-Balance
-Smooth double action triggers that respond well to tuning
-Readily available repair service and parts
N Frames (Model 27 and 28) are well suited to a steady diet of full power magnum loads. K Frames (Model 19 and 66) are best for mostly .38 Special with moderate .357 usage.
The L Frame guns (Model 586 and 686) are also good and can handle lots of hot loads, although they nearly always have full underlug barrels with a more front heavy balance.
Ruger GP100s are good solid guns for the most part, but the triggers aren't as smooth as a S&W and I don't think they look as nice.
Colt Pythons are well made and very accurate, but have delicate lockwork that is more prone to having timing and lockup issues compared to either Ruger or S&W. It is also difficult to get parts or service.
I would stay away from Taurus, as they are more likely to have issues and there is no source of spare parts or warranty/repair service in Canada. Also, they have crummy triggers.