Scotty P has beaten me to the punch with an excellent post showcasing the differences between the two. All I will say is take his advice: get the First Edition if you can and leave the RID version for the kiddies.
On a somewhat related note I now have multiples of two characters: Cliffjumper and Bumblebee, and I am at a loss as to what I should do. I've really never had this problem before because I have often refused to buy different molds of the same character ever since that crap started back with Beast Machines. I wonder how other people deal with multiples? This is especially difficult because they are of the same size class! Ah, tis such an onerous existence we transfans lead!