Concurring that pumping made my real life erections better. Much better. I am unable to pump now for privacy reasons, and while my erections are good, they were much harder when I was pumping regularly. In addition I had a lot of night wood — it seemed as if I was hard most of the night.
Pumping is an excellent exercise if you approach it correctly and listen to your body. What has worked for me:
A good warm up and warm down with heat
Several short sets rather than one long set (I do either 2 or 3 ten minute sets)
Massage to full erection between sets.
Pumping a low pressure (I pump between 2.5 and 4HG. The thunders recommendation is to stay below 5HG)
Wrap the cylinder in a heating pad or similar to keep it warm.
Massage to full erection after your workout for 10+ minutes
Much of this I learned from the excellent posts of gprent, avocet8, Lampwick and all of the other thoughful longtime pumping vets on thunders.
The newbie process for pumping gprent mentions is here:
Vacuum Pumping 101
A related and very interesting thread about improving erections for those who have ED is here.
Vacuum Pumping when you have ED; the short version, according to Avocet8
Personally I did manual PE for 2 or 3 months before starting to pump. As my penis is a little sensitive to PE, I followed the recommendations in that thread, but doubled the time I took to get there.