I read Ice Station and Temple when I was younger, and thought they weren't too bad - low-brow, certainly, but readable. I picked up Area 7 as an aeroplane read a few months ago, and didn't make it past the first hundred pages.
It's appalling! The man couldn't write his way out of a wet paper bag. Frankly, the fact that he was published at all demeans everyone in the publishing industry, AND the reading public.