DRE performed by a doctor can be uncomfortable as well as painful given the clinical nature of the examination itself. Doctors usually don't allow time for the anal muscles to relax.
On the other hand, if done properly, slowly and gently, prostate massage can be highly beneficial to your prostate health and highly pleasurable as well.
For Safe Prostate Massage to be enjoyable, anal muscles including anal sphincter need to relax. Plus quality and quantity of lubrication.
The actual prostate massage starts with the application of lubricant onto the anus and gently pressing middle finger against the anal area so that it starts to relax. Slow, circular motion is applied. Few minutes of the usually tight anal muscles makes them relaxed and to most men the sensations this brings are in itself pleasurable. You prostate gland is filled with nerves and muscles and is considered a highly erotogenous area.
After a while and at the right time and the correct angle, index finger is to slide in easily. Initially this may feel like an unusual feeling and you will adjust, letting the sensations and feelings unfold. Pressing gently index finger upward till feeling the prostate gland. With finger moving forwards and back, in a circular motion, slowly and gently, being such a delicate internal organ.
For the first time prostate can be massaged for 5-10 minutes. Proper prostate milking can be 15-30 min where prostate fluid aka prostate milk can often be seen coming out either via penis or anus.