I'm gonna pick up a couple of limb clickers. I see 3Rivers has two different models but they both look very similar. Is there any difference/advantage of one over the other?

They are essentially the same except the Cricket is shorter--no other difference. I use the Cricket because I just prefer the shorter length of the base which mounts on the bow limb with double sided tape.

Both work great!

Just cut the longer one down they are pretty much the same. Also get rid of the chain and replace it with D loop rope the compound guys use.