1. Never had one leak on me yet, and they sure make life easier when moving and changing things around. A good investment IMO.

2. Eventually it seems all valves will end up getting clogged at some point, not sure if one would be better than then other. Best defense would be cleaning the pipes every now and again, you can get commercially made ones, or one of the flexable shotgun cleaners work well, even a rag and string would help . (just don't run it through your shotgun afterwards :D)