This is not Batemans best work, and given how good his best is, that givens him room to fall a long way short.
It's taken me a while to figger out why Maid in the Mist just didn't click, but in retrospect it's the unreality of the tale. His best books (and I really recommend Driving Big Davie as his funniest, or Empire State as his masterpiece) build up to a madcap pace. They start in a small, grounded, believable situation of a slightly nutty Irishman, before spinning off into wonderful moments drawn from the quirks of life. (as a guy who once got caught on a beach with my `gf' by landing crafts full of marines, I can testify that really crazy things DO happen).
Maid jumps in at the deep end, and that just didn't work for me. The eponymous character herself comes out of the blue early on, stretched my incredibility too far, so the tale just didn't carry me along.
Now don't get me wrong, it's not a bad book, but it's not great either. Bateman has given us greatly superior writing in small episodes that grow up into pure mad genius.