Zenit TTL, Helios 44M 58mm f/2, Kodak Portra 160
So far I am greatly enjoying using the Zenit TTL. I love it's design which I find to be rugged and simple.
The Zenit TTL is a 35mm SLR from the early 1980's with a M42 (aka Pentax aka Praktica) lens screw mount. As it's name would imply it features through-the-lens metering including automatic aperture stop down with newer M42 lenses.
It's metering is built into the shutter release. Partially pressing it down engaged the meter as well as stops down the lens aperture, and then pressing futher releases the shutter.
This is different than say the Pentax Spotmatic SP which has a separate lever to engage the aperture and metering. Either method works fine, though in practice I don't check or change exposure every shot and therefore find the Pentax a bit less disruptive.
The metering itself is a bit suspect. I believe it averages light across the whole frame and seems to key off of any bright spots. It also engages at a slightly different point than the aperture stop-down.
I haven't had any problems getting good exposures from it, but I have had to double- or triple-check many shots just to be sure I knew what it was thinking.