I'll be brief.
i put in the Aneros and was sure not to push it in all the way. I didn't clench, I just breathed normally and tried to "tune in" to what was going on - full awareness.
It began to massage me on its own. The pleasure ramped up quite quickly. Then there was a definite "peak" where it was pleasureful. I kept expecting something to leak out of my penis but nothing did. The P-orgasm lasted for maybe 30-45 seconds?
My next session had the "ramp-up" but I couldn't make it over the edge.
The aneros is def too long though - for me. And I'm well over 6ft.