I've got an SE Singlecut, which I've had since December 06. I tried several before buying it, to get a decent idea about build quality etc. They are very well made guitars. The construction is as good as some guitars I've seen costing twice the price, and the finishing is decent. The wiring was very neat too, accurate soldering and the wires tied with a cable tie. The major weak point, in my opinion, is the tuners - they aren't really up to much if you like to go for the big bends. I changed mine for a set of Sperzels. Pickups are pretty decent for the price point too. I swapped mine for Holy Divers, cos I wanted that specific sound.
I also tried several Customs when I was hunting around. I liked the hardtail versions, but the trem on the trem variant felt very cheap and insubstantial, particularly the arm, which felt like a pipe cleaner. Now, having had experience of the genuine PRS trem (on my US Tremonti), I think my initial impressions on the SE trem were about right.
However, for the money I still think they are excellent guitars, particularly with some of the deals that can be had on them at the moment.
Hope that helps.