I have a Kiev88 and a Hartblei (like and Arax - a modified Kiev). Both are reliable. If you get a Kiev that is working, it is probably fine since it was one that worked. Hartblei (or Arax) just takes the factory bodies, and makes sure they work properly before they deliver it (and adds modifications, like the cloth shutter).
Metal or clothe shutter: the reason Victor Hasselbald (and thus Kiev) used metal shutters was to prevent holes from being burnt in them by the sun, which happened to his Leicas. Because the blads did not have an instant return mirror, the shutter is exposed after the exposure, and if the sun in focused on it for any lenght of time, you can easily get a hole in a cloth shutter (think tripod mounted with the sun in the picture). Not so with a metal shutter. The 200 series Hasselblads came with an instant return mirror, which blocked the shutter after exposure, so they could switch to a cloth shutter with less chance of sun damage.
The disadvantage of the metal shutter is that it is easier to damage it if you stick your finger through it. (This is true with 35mm SLR's too). The fact that it had a removable back made this an issue.
The cloth shutter is quieter (or has a softer sound). Leica users do not have a huge issue with sun damage, but if you ask any leica repair house, it certainly happens. But Leicas probably spend less time on tripods than Hasselblad/Kievs. If you are careful not to leave the camera with the sun in the frame after an exposure, and/or you have fuble fingers and like to chang the back a lot, a cloth shutter is probably a good idea. Personally I'm fine with either, but if I was buying one today, my personal preference would be the cloth shutter.
