They work good not too hard to install, and they look terrific. However, it is more challenging to respool the cable after deployment due to limited visibilty of the spool. The quality of your wrap on the drum greatly effects the holding power, pulling power, and overall durablity of the winchline. If you don't ever intend to get a steel front bumper, the hidden winch is a good alternative, but not a superior one. However, having a winch when you need it is WAY better than wishing you had one.
There was a good write-up about a year ago on LRRforums where someone installed one, had an issue with the fitment, sorted it with help from Rasta, and was able to install it. There are one or two guys in my SCLR.org club with a hidden winch and they like it.