Zenits are wonderful cameras. Yes they are a bit crude, primitive and simple , but using them gives numerous advantages over other slr's. I would definitely leave them at home for sports or action photo's. I have the following zenit 3m, c,b,e.ttl, and 12sd.
1- They will slow you down . They are the perfect thinking mans slr .
2- The viewfinder on the early models are bare . This puts all your attention on composition.
3- The M39 and M42 mount opens you to a new world of vintage optics.
4- Lets face it they are cool !!