"It's too gory".... I believe police work could be quite gory at times, nature of the beast.
"it's too long".... This may have something to do with a metro' detectives ridiculously busy work load.
"I didn't like the dialect."... They're Scottish, they're supposed to be dificult to understand.
Seriously though, I loved the idea, I liked the characters and disagree that they weren't well formed, though a little gallows humour wouldn't have gone amiss (a la Mc Bride) and I believe Oswald to be a fine story teller. My one gripe though were the coincidences, they were just a little too much and too often to ignore.
The sister of his best friend just happened to own the clothes shop, the cufflinks just happened to be made by the one jeweller he goes to , his grandmother was known by every character mentioned in the book, well, I could go on, just like the coincidences really, but it's not necessary because if you read this, and you should if you enjoy Rankin, McBride, Billingham, et al. You'll see.
If only real murders could be solved so conveniently.