I've run a pair of 06 Pike Air 454s for a couple of years and am very happy with them. Despite being air sprung, I've got no complaints about their plushness (although they do take time to bed in), however I have had niggles with the compression damping.
I've noticed that small amounts of fluid can leak from the Motion Control dial and the forks gradually begin to spike on high speed impacts, necessitating a premature service. I'm told that the Motion Control O ring seals can be fragile, which causes this problem. The motion control gubbins themselves are very, very simple - a good thing IMHO.
Otherwise, the stanction sealing seems good along with the general build quality - certainly much better than my old Pace RC40s in this respect.
A friend who works in my LBS's workshop has commented on 2006/7 Marzocchi forks being a tad temperamental. Marzocchi has relocated it's fork production to Taiwan in the past couple of years, which may/may not have some bearing.
Ah, RS have had manufacturing facilities in Taiwan for sometime, so the build processes are tried and tested.
There have been inherent problems with keeping tabs on manufacturing tolerances for existing products being subbed out to a new manufacturing facility in the Far East - just ask Manitou.