I thought it was pretty decent, but it's one of those overtly literature alternate histories, if that makes any sense. Roth wasn't really that concerned with the setting, IMO, and was decidedly more interested in talking about things that were close to happening anyway (rampant anti-Semitism on the urbanized American East Coast) than the consequences of his alteration. That's fine, and the story itself wasn't bad at all, but it wasn't really my cup of tea.
The fact that it was about an alternate 1940s, of course, didn't help.