It's not for everyone, but when performed by someone who knows what she's doing (and has short fingernails!) it can be mind-blowing when combined with a HJ or BJ.  And there may be health benefits, for example...

Done with a bj or a hand job and it can be mind blowing if done right.  I've had several occasions when it extended my orgasm and made it very intense.  Had several providers who seemed to enjoy the spasms made on their finger while performing.  Just be clean down and in there and relax.  Good providers know how to get the rectum to relax and listen to their customer.  Enjoy

But I have trouble keeping wood during prostate massage and the orgasms are less intense.  I know a few guys that are like me, but others seem to like it a lot.  Just my two cents.

My first post on this board.  I'm 57, so you can refer to me as "The Kid" if you want.

I've had a few prostate massages and it's can produce some mind-blowing orgasms, if performed by a talented provider.  One of my former ATFs was also into tantra which made the combined techniques even better.

I know it not for everyone, but you'll never know what you're missing until you give it a try.

which was an unbelievable experience. I didn't know she was going in.
Did some light touches in the general area and then slipped a condom
over her finger, lubed up, eased it on in there and proceeded to give
me an unforgettable sensory delight. I think she was a nurse.
I asked one of my favorites recently, she had never done it,  
and after a few minutes of fumbling around announced:
"I can't get in." She couldn't navigate around those infernal internal hemorrhoids!
I appreciate her being willing to give it a shot.  
I'm going to ask another lady someday and hope for the best. If feels too good
when done right and combined with the before mentioned activities.

I happened to be reading this thread when I get that oh so familiar robocall.  I press 1 on my phone & some guy comes on and says hi.  I asked him if he wanted a prostate massage.  Long pause, then he says "Noooo?"  I asked him if he knew what that was, and he hung up on me.  How rude!
 

that you can buy sex toys specifically designed for prostate stim.  Mines has a tip at the end which presses up against the prostate, so it has to be inserted in the right direction.  Has a rechargeable variable speed vibrator in it too.  For those times when a womans finger is not available, it can be great.

Benefits of prostate massage for mature men.

This is, quite possibly, one of my favorite subjects and my personal area of lay-person expertise.

So prostate massage is controversial in medical circles because the research changes its mind every few decades about whether it is or isn't beneficial and under what circumstances. Bear in mind that checking your PSA levels used to be the gold standard for identifying possible prostate cancer and that has recently been abandoned because they found it wasn't as accurate as they thought.

So if you have prostatitis or have had prostate cancer, prostate massage may NOT be for you. Check with your MD first. He can explain all of it. I would explain but it would take me 3 pages of typing and boring info. If you are clear for those things, GENTLE prostate stimulation is always a good form of self care because there is not one part of your body that doesn't benefit by increased circulation and TLC.  

 
There are a number of small things that should be taken into consideration when giving prostate massage so if you are giving yourself a prostate massage, please consider these things first:

1) Nothing sharp. The prostate is a gland and the tissue around that area is paper thin (or thinner). Small micro-cuts and trauma will not contribute to a healing process or a pleasurable experience later.

2) It shouldn't be uncomfortable. If you feel discomfort, it may not be a prostate issue but an internal hemorrhoid issue and you don't want to compromise those.

3) If it is painful, just stop. Do not pass go. Do not collect 200 sighs of pleasure. Go straight to your urologist for an exam. There may be something else that is serious going on.

4) If you use insertables by yourself - make sure there is a flange at the bottom of the thing! More emergency room stories start with "and then they did an x-ray and found a ____ in his ______" up to and including electric toothbrushes that were still vibrating at time of arrival. For the record, the poor bastard lost part of his colon as a result of this but not before almost dying from infection when the colon was perforated by the toothbrush bristles.... yah. A flange or something that will remain OUTSIDE your body and not slip inside while the rest of it is in. Solo play is fun but only if you do it safely.

5) Be generous with the lube. Next to an experienced prostate friendly provider, it will prove to be your best friend.