I bought my first Aneros, a Helix Syn, about 1-2 years ago. In the beginning I was very unfamiliar with anal play (straight guy in 20s) and was just fooling around a bit. I remember that inserting into my butt made me uncomfortable. I also didn’t really get any good feelings from it at the very start.
After a few sessions I bought a different model (can’t remember which one exactly) and ordered poppers, seeing that many people have had better results with them. In the next sessions I had a nice feeling of pressure inside me, especially after a sniff of poppers (I guess that was the aneros pushing onto the prostate). I also felt some very slight involuntary contractions: I involuntarily contracted some muscles down there and it felt nice, but after a few seconds the contraction would stop and that was the end of it. I only got those contractions with the MGX Trident and Maximus Trident.
After that, I didn’t get any further for a long while, I even tried using the Aneros while on a light-medium dose of LSD, but the experience with the Aneros didn’t change while tripping, it was the same as sober. Because of the lack of progress, I stopped using the Aneros massagers for a while.