Both wands are cool for anal/prostate stimulation. The three beads make it really easy position to hit the prostate and when used in an gentle motion against the other areas or your inner butt it can be very pleasant to very intense. The big end can sometimes be a little bit poky at times but it can also be very intense and different from the other beads.
Cautions!!!: lots of lube, more then you think until you are experienced, applied with a with a lube shooter to put the lube inside, clean yourself out before hand, and there is a nice how to video by Nina Hartley on how to do it. Sorry, I did a quick Google search and the quick was my unwillingness to wade through the links beyond the first few to find the it. Again - sorry, but you should try and find it, it has a wealth of good info. Check her facebook page.
Last Caution!: It is not like a wank where you might be tempted to bear down, get a big push and over the waterfall you go. Stay gentle and everything should be very pleasant. Give yourself time to get use to it, find what works and what doesn't and it could be really really really good.