Canon F-1n (original). I *loved* the partial spot metering system on this camera, and it had a silker, more jewel-like feel than the New F-1 that replaced it.
Canon EOS-1V: The Porsche of AF film cameras, and oh, what elegant lines! (But then, I haven't used an F6... )
Nikon F2: for being the ultimate "system camera" and setting the bar for all others to reach.
Leica M3: for its glorious long-baseline rangefinder, flare-free viewfinder, and ease of focus with fast lenses.
Leica M6TTL (this applies to any modern Leica M): for reminding us that cameras used to be considered fine precision instruments rather than consumer electronics devices...
All have very little to get in the way of making images. But, the FM3A is incredible with full auto aperature priority, great ttl flash, great metering even at 1 minute plus and no batteries required if it comes down to it.
I have used the OM-1, 2, 3, 4, Nikon F2, 3, 4, 5, 100.......they all pale compared to the bomber simplicity and battery free FM3A.
One of the most versatile SLR's was the Leica R4.Many lenses still sought out for R9, film and digital.
With the 35mm 2.8 it was as small as an M and the color and reliability were great. Had AE and actually, there was nothing more that R9 could do.
Still use mine when I dig into the fridge for some older film!
The Nikon F3a was hard to leave - it felt like it was molded to my hand. Then I tried the nikon F5 and I never went back. Ok the F5 was hard on batteries, but what a wonderful camera to use.. I was unhappy when the world turned to digital and I had to sell the two I owned.
my faves are the n1 and nd contax. for all the reasons lotusm50 mentions. the leica m has its place too, but needs some form of handgrip. the g1/2 were v good in almost every way except the squiny viewfinders and innaccurate low light focusing with the 90mm - otherwise close to ideal, with exceptional lenses. liked the nikon fm2 (nice and simple) and was impressed by the f6. never got along with canon ergonomics since eos.
My new (demo) 1v Hs is in the mail (for approx 1/2 of retail!). I bought it today after scanning 40 year old negatives from my Nikon FTn on my new Epson V750 @ 6400 dpi. The V750 makes a 16 bit 505Mb color file from a slide! The image compares very well with my 12.7Mb 5D files with the natural film look and, with slow reversal film, apparently more detail.
I have all the modern Canon lenses and thought that the 1v Hs would be a natural choice to retain film capability while owning a Camera that I could not (then) afford.
It's interesting that while pulling film through the body the 1v Hs will shoot 10 Frames per Second-faster than the digitals (with no film to transport).
I am also looking forward to using those fast L lenses with a 100% super fine/super bright viewfinder. I plan to use my 5D's histogram/LCD as a manual light meter.
The Nikons were out for me because exposure compensation requires taking your eye away from the viewfinder before applying your third hand. Canon hadn't great glass across the range. Leica's too heavy and expensive and you have to like that dreamy look. Contax had the best combination of features and controls designed around usage (thanks to Porsche Design), glass and price. N1 never really got off the ground systemwise so it's second. RTS III had intermittent front/back focus problems owing to vacuum plate. RTS II with a Beattie Intenscreen was the clearest viewfinder I have ever used, and you just couldn't fail to nail it every time.
Leicaflex SL: nearly indestructible construction, smooth and quiet, viewfinder to die for, and it can use most of the current Leica-R lenses with slight modification.
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