I've tried with fingers on myself with pretty much no results. The key is you have to be incredibly relaxed, and it's tough to do so while you're all contorted. That's what makes the Aneros so nice, you just put it it in, lay down, and let your PC muscles go to work. You also have to go into a session with no expectations b/c it seems like the more you try to will yourself to a prostate O, the more elusive it becomes. It does take a lot of patience though, occasionally people will get amazing results in their first couple tries, but more often it takes 1-3 months or maybe more. Aneros has a forum that covers pretty everything you'd want to know. Just approach it with the same vigor that you do PE and I promise the results will be crazy.
If I had to compare my best ejaculatory orgasm to my best prostate super orgasm, I'd probably say the latter was approx. 20x more intense. Imagine about 30 minutes of full body intense waves (compared to the more localized 15-20 second traditional O.
Honestly, being ok with prostate play just introduces so many more ridiculously pleasurable ways to have fun with a female partner. I haven't been able to try these yet, but at the top of my list: fucking her while wearing an Aneros (which I hear is great), fucked by her wearing the Feeldoe, a double dildo that vibrates so we can both potentially have crazy orgasms, wearing the Feeldoe myself (in my ass) and using it to penetrate her ass while I also penetrate her with my cock (so we're both being DP'ed essentially) and on and on. I mean every session doesn't have to be about anal play b/c I think a lot of women might not be into that (although I wouldn't mind at all if they were cool with this), but it just gives you so many more options.
Fuck, I need to find a steady girl that's cool with this.