Well, I've tried it on Mac, Linux and Windows and it only blocks a minority of all flash files I've encountered. It seems especially bad with youtube and vimeo files embedded in blog posts.
In fact, I don't think it really can work in any real sense as an actual blocker since chrome doesn't provide an API for that. As I understand it, the best it can do is to remove the flash after the page has rendered.
But what you've said is true, FF's FlashBlock has much better control over Flash because of the control it has via the API. Chrome doesn't offer the same level of control to extensions, so they're all just going rewrite the page on load. That's been good enough for me though.
The point of Flashblock and NoScript is security without sacrificing usability on trusted sites. Yes, it lets you ignore the Flash, but it doesn't actually protect you because the Flash is still loaded.