Reading all nine pages of this thread, I found it interesting that "screw-mount" Pentaxes didn't get mentioned till fairly far along....
My SLR experience is limited compared to many who responded, but I will share my thoughts based on what I have found...
The first SLR I ever used was my Mom's Canon AE-1 Program, which she bought around 1983... a nice, friendly camera with a choice between full manual, Aperture-priority, or full AE. Nice glass too.
During late high school and college years, my user camera was a Kodak Retina IIIc outfit.
My first SLR was a Minolta XG-1 outfit I acquired at a rummage sale, and it came with all kinds of toys: motor-drive, bevy of flashes, several Rokkor lenses, including a nice zoom. It is a ncie camera, although a bit fiddly to work with. The electronics started getting dodgy, and the light seals are beginning to crumble, so I put it aside.
Next SLR was an Exakta Varex VX, with WL finder, prism, CZ Jena 2.8/50 Tessar, and Schacht 135 Travegon. I have since accumulated several more bodies (most with bad shutter curtains 🙁 ), and some nice glass: Zeiss f2/58 Biogon, Zeiss f2.8/35 Flektogon, Schneider f4/28 Curtagon, f1.9/50 Xenon, f3,5/135, and a big Vivtar zoom, plus a host of other miscellaneous gadgets.
The Exakta is great in its historical aspect, and the sheer number of adapters and accessories compatible... and its full mechanical nature make it fairly feasible to maintain and repair. It's biggest shortcomings are the slow lenses, due to the relatively small size of the lens-mount, and the left-handed nature of the operating system.
Then came a Minolta SRT-101, which I haven't had any shooting time with, due to sticky shutter works.
Finally, an Asahi-Pentax Spotmatic 500... neat cameras, that seem to be reliable, inexpensive, and offer a decent range of excellent lenses. The TTL metering is simple.
The Spotmatic became my everday shooter SLR, so I guess that makes it a "favorite"...
The Exatka is my favorite from a nostalgia / quirkiness standpoint.
A good friend, who is a professional photo-journalist swears by Nikon F's, though he has moved-on to Nikon AF digital for most of his work. He was quite fond of Spotmatics in his pre-Nikon days.
This thread has been an interesting read...