i've gotten transparent detail and that seems pretty smooth and allows for light pipping

frosted detail is the cleanest most smooth but brittle

i've gotten the punch/counterpunch kit (head and hands), guzzle kit (chest and head) for ROTF hailstorm, roadbuster head for crossovers iron man/cap, pyro head, chromia head for prime arcee, idw first aid for prime ratchet and iron fist with bullet hole head

they're all pretty niffty and allows you to add more characters to your collection