This is one argument I've always loved :-)
I was a Canon camera tech back in the days of film, and one thing that often came up was "which is better - Canon or Nikon"? I was a bit of a maverick, as I actually used Minolta cameras (SRT's) at the time, and had previously used Nikon F's and F2's. I then changed over to Canon because a) I could borrow any lens from the loan cabinet, and b) when one of the newspapers sold off all their Canon gear I got an amazing deal on NF1's with motor drives and a range of lenses form 24mm to 300/2.8.
But I digress. At the time we (the 2 techs who actually took photos) had an a similar opinion. Both camera systems were relaible and capable of first class results.
It was the lenses that were different. Nikon were sharper wide angle (between 14mm and 28mm). From 35mm to 135mm both systems produced pretty much identical results. From 200mm and up Canon were ahead in terms of results.
I know this is going to cause an argument, but it was backed up by many of the photographers we spoke to who had shot with both systems (quite a few of whom owned 1 system, but shot with the other system "at work").
As for me? I currently own a Old F1, a New F1, a Nikon F (I sold my F2), a Nikkormat FTn and half a dozen Minolta SRT's. Nearly forgot, I've also got a Pentax MX (which many people consider one of their best ever cameras). And a OM1 Olympus (now that's a under-rated camera system).
I've got various lenses for all the systems.
Bottom line? I can use any of the cameras listed with any of the lenses I own, and you can't tell the difference in the final result in slide.
Prins? Well that depends on what enlarger lens you use......and that, as they say, is another story....