How familiar are you with anal play? The Sasha Grey plug is considerably larger than the other two and makes it not for beginners. So if you are looking for some stretch back there, then that might be the right choice. If you are looking it wear it during intercourse and have it push your partner toward your g-spot, then the Icicles #14 might be the way to go. If you are looking for a long term wear plug, then Moon shine might be just the ticket. It all depends on what you are looking for.