I too, like the others, found the red rear sights to hard to see in subdued lighting. I found some day glow (not really flouescent) paint at WalMart (or a hobby shop if Wally World not available) and used a toothpick to dab a little 'green' on the rear sights. Liked the yellow on the front sight (C-9) as it makes picking up (aligning) the three sights much easier for me - and gives a contrast between front and rear sights. Had painted an orange ring on the front sight of my 995 for quicker target acquisition, but that was made obsolete when I added a Sightmark Red Dot. Shooting both is so much more fun now that I can see and hit the target!
I used some glow in the dark nail polish the girlfriend had sitting around. Not the greatest fix ever but it gets the job done and if/when it goes bad, a quick rub with acetone and a reapplication will fix it.