Not sure if this will work for anyone else, but here goes.
Recently with Aneros inserted, I realised that if I placed my palms flat on my stomach, then slide them forward till my fingers came to the base of my penis, and pressed both down and forward (so that your fingers press into that soft spot at the base of your penis) I could put pressure on my prostate from the top and bottom (so to speak). Doing this repeatedly traiggered many prostate O’s, and eventually led to a HFWO.
Recently, I realised that if I do this same technique without the Aneros inserted, I can trigger an amazing feeling similar to the aeros pressing against the prostate. Its subtle, but its there and real. By keeping some constant light pressure on this spot and not letting up no matter what, I have had the most intense super o’s of my life. We’re talking seeing colours, altered perception, near out of body experiences. Typically the super O’s start at my second or third orgasm from this technique, so about 5-7 mins in.
Give it a try and see if it works for you.