It's my second favorite toy overall, and my favorite that I can use casually. The size and shape is similar to a long finger, which I think is optimal. It slides in easily. At full insertion it hits that sweet spot better than anything I've found, but I'm inexperienced.The vibration is INTENSE. I really really like it. I've tried several toys and this one stimulates the prostate expertly. I reckon the spinning simulates someone rubbing the prostate.The only downside is that it doesn't have a... Idk... Ridge or something to keep it in and secure like a butt plug. Butt plugs aren't coming out by accident, but this one does sometimes need a hand keeping it pressed in fully. Or maybe sitting on it, but I like laying down.