I picked up an Aneros MGX last year and have tried it a handful of times.
So far I’ve managed to get some pleasure from it but not the elusive pgasm – whether dry or otherwise.
I’ve tried manually moving it using the kundilini handle even though I heard it’s not recommended. I’ve tried contracting and relaxing my anal sphincter.
I’ve tried various positions and various kinds of thrusting.
Someone that I picked up on /r/prostateplay however sounded very promising.
Someone commented that you can do literally nothing – as in just lie there – and the natural peristalsis of your anal muscles will sort of manually push the toy in and out therefore stimulating your prostate.
Obviously you have to be in the right frame of mine. But… If the more vigorous methods of stimulation have thus far failed me does doing nothing other than lying there with it in hold any potential for success?