I saw the first two. #1 pissed me off to an extreme degree, because not an effing thing about the book made it to the screen. Not. One. Effing. Thing. I mean, the main character of the book was ex-special opps or some such. In the movie, Corey Haim was the main character. WTF? Plus there was a third "Watcher" lurking around (Michael Ironside in a performance that would make John Voight cringe) that had nothing at all to do with the book. I'm sorry, but this film "licks the sweat off a dead donkey's balls."
#2, however, made me at least a little happy. Marc Singer ain't everyone's cup'o'tea (but sometimes he's pretty cool and where the hell is my If You Could See What I Hear DVD, anyway?), but he was sure as hell better than that Corey Haim/ Michael Ironside clusterfuck. Besides, Watchers II at least attempted to keep itself to the story in the book, which was very good. For me, this made it possible to overlook the low-budget kludge-bomb of special effects and just sink into the movie.
Perhaps, if I could find Watchers II all by itself on DVD, I would purchase it and watch it again. But I will not have that Corey Haim crap in my house. I'm afraid it's awfulness might seep into some of my "good" movies.
((edited to say: "Kludge: Look that up in your Funk & Wagnall's."))