Rail Ring's my number 1 choice, because my aim's pretty good. I love shooting from a nice cliff/platform. ^_^ And that rush I get when I shoot someone RIGHT out of the air during a spring launch just makes me wanna shout "BAM!" XD
It's also very deadly when combined with either a bomb ring, or an auto ring.
Problem is, it's darn near useless in close combat, since you can only fire once every 2 seconds. X_X
Auto ring's my second choice. It rules in close combat, but your rings drain faster than a cup of milk in the hands of a 9-year old with chocolate chip cookies.
Mmm... Cookies. ^_^