I have bought two of the prostate massagers, one of the less expensive and the Aneros MGX. The MGX is the BEST! When I tried it, I could not believe the sensation, just a little lub nd it slipped right in!, stayed in place and with just a few muscle movements had me on the edge. The shape has everything to do with its effectiveness. The less expensive one was round, but the Aneros is shaped to give maximum pleasure. The angle it set in gives mose intense contact. The less expensive one got me off ok, but the Aneros almost made me orgasm twice, one after another. I recommend this one for anyone who may enjoy the intense feelings of an orgasm while having a prostate maggage. Martwick