Hey, sorry I'm late to the party? What did you end up buying?
If you're still looking I can offer some suggestions.
The aneros toys are my go to when I'm looking to play with my prostate. Particularly the syn toys. The eupho syn is longer and thinner and my experience with it has been very...gentle, I guess. The helix has a fuller body, and I feel like it'll slam into my prostate when I'm cumming (which is a good thing!) while the eupho just kind of focuses on one point and exploits it. I have had zero luck with my orogasm though.
The revo 2 is great but hard to find. I got mine shipped from overseas. The rotation is really unique and feels great, but what makes me cum is actually the way it plays with my sphincter. When I'm on all 4s, the weight of the toy puts pressure on the bottom of my hole, and thus pressure combined with the turning and twisting inside puts me over the edge. I hear that the stealth is just as good.
The billy has made me cum, but only if I already came from an aneros or revo 2 session. That's just me, but it's the best vibe I've had. It does a great job of being large enough to massage the walls of your hole without stretching you too much that it hurts. And the tip allows you to hone onto specific spots that you come across while exploring your ass. It's the best.
I just purchase the Lelo Bruno and the Loki today, they seem to be more of the "lay down and relax" type of vibe, rather than the billy which is more of a "fuck your self gently" toy. Check those out too!
I have the njoy wand, and I like it, but not as much as everyone ear does. They're crazy about it. But I'm much more into vibes and it sounds like that's what you're looking for.