It was a hard choice choosing one of these. They are plastic, so they won't flex to fit you, and they are expensive so you don't want to pick the wrong one.

I chose this because it was thinner than the others, which makes it easier to insert, although some might prefer to feel more "stuffed". I also liked how it didn't have that curl at the back like the Aneros toys do, because it gets in the way when you're moving to a different position or getting up.

You should definitely stick some fingers up there to find out exactly where you naturally have room to place something, and try to predict which model would fit.

Three things to consider with this particular model are the shape, the ribs, and the angle at the bottom. The shape is pretty round, so it can twist inside you a little. I sometimes will grab the tail end and wiggle it for the pleasure of it, but a more unidirectional model would aim it forward better. The ribs at the bottom never touch my skin, so I don't see the use of them. They catch lube, which is good, but make cleaning harder. The angle of the bottom is the main flaw for me. It digs into my body. I thought this would be good because it should squeeze the prostate between the two ends, but for me it didn't affect my prostate, it just pressed and chaffed my perineum a lot. By the end of every use, I am aching. This seems to be the only model with such an extreme angle luckily. The ball is an advantage over the aneros toys.

Shoppers should know that not everyone who buys these toys will ever have a prostate orgasm in their lifetime. From what I've read and listened to, it's pretty uncommon even with the most expensive tools. Some get them very easily, and will assume others "aren't doing it right", but the less lucky will learn after much learning and effort that not all bodies are the same. My guess is that if you get a LOT of enjoyment out of anal play with fingers, penises, or dildos, you COULD have a prostate orgasm with one of these. If you kind of enjoy anal play, this will make you feel good, but won't magically quake your body with pleasure. Keep reasonable expectations.

This wasn't the right fit for me because my prostate feels much lower than the top of this. If it were half as tall, it might do me better. The angle of the bottom also didn't help.

I want to point out that mine doesn't quite look like the pictures. Mine has that matte texture on it that you can see in the orange & red pictures. Despite mine being purple, it did not have the shiny smooth surface that you can see in the black and purple pictures, and I think I would have liked those better. I got this in Dec 2010, so they may all be matte now.