I mostly do my own becasue it's easy and cheap. Just changing the damping oil and lubricating oil in the lower legs makes a noticeable difference to the feel of the fork. Same for the rear shock: A quick aircan service and I can feel the extra smoothness.
As for professional servicing, I've discoverd that in general, a RS fork will go a bit loose on the bushes fairly quickly - 3-8 months or so. Then I send them off to TFT, they'll resize the bushes as part of a service and they come back like new. I found this only really ever needs doing the once. Once the fork has bedded in and the bushings resized they seem to go on forever without it needing to be done again, as long as I keep changing the oils now and a gain. I do it once or twice a year, or before a trip to the Alps etc.
I've never had any big problems with any of my forks (1x Rebas, 1x Recons, 2x Pikes, 1x Lyriks, 1x Fox 32 Vanillas) the worst being damping oil leaking on my lasty set of Pikes. I sourced some O rings for a couple of quid and fixed them myself.
It sees RS and Fox forks are generally well built and last very well if looked after.
My Vanillas get the most use and at about 3 years old are now showing a bit of stanchion wear, but I've only fully serviced them once in that time (Naughty I know!) and it's not affecting them at all that I can see or feel, so I'll carry on using them until they die. I have no reason to think they won't last me another 2-3 years.