The other important distinction would be that an RR allows you to view the chips and make a decision (based on what you personally collect) to take or ignore a chip.

A shotgun is such that you get what you get. I just received a bunch of shotgun chips from Doug's shotgun. I received some that I already had, and some that were new to my collection. I am sure that the ones I sent to the other 9 players will either be one of the same.