Read most of the "Merrily Watkins" books, and have a few of his other works as part of the "to read" mountain. Liked them enough to go up to Hereford for a couple of days just to look around and see some of the locations (Hereford centre=bit of a dump, surrounding areas quite nice, though). Got to see the cross where the severed head was left, amongst other places. The "terrible" estate (Plascag?) didn't seem that bad, though.
I must admit that his style is beginning to grate: the (admittedly tense) build up to... something horrible, followed by a chapter of something different and then the resolution to the cliffhanger (which is often a let down). I still find them enjoyable, though I wish he would go for a more out-and-out supernatural tone.
It's a shame the proposed TV show seems to have stalled, as it may well have avoided some of the books' annoyances.