Dammit. I had a pretty lengthy review and then lost it. Oy.
I liked it. Desperation's moodier and more atmospheric; this one is more fast-paced and gory, but over all it's a fast read and a fine novel. Desperation deals with the darker sides of human nature and the universe, while The Regulators deals with the human psyche in stressful situations. If Desperation is Lovecraft, The Regulators is Bloch.
Overall it reads like a fast paced (if gory) supernatural adventure story, with occasional lulls that explain the backstory and events leading up to all hell breaking loose.