My hubby had a vasectomy before we were married (10 years ago...before we realized the potential for long-term harm). We've (actually he's) used this same prostate massage tool for the last few years and it's been an EXTREMELY positive experience for him.
And besides the health/prostate benefits, the quality (and length) of his orgasms is, well frankly, absolutely enviable when he's utilizing this tool during sex. It almost makes me wish I had a prostate gland so that I could get in on the "healing" LOL :)