Grammar checking software

I am looking for a grammar checking software that would work with Scrivener so I can cut myself off MS Word (finally!). However, when I search around, I can only find a few (Grammarian, etc.) and they haven’t been updated since last year. Has anyone here used these apps? If so, how well do they work? Are they worth the money?

Thanks!

Heh, I just started a thread about this stuff a day or two ago. Haven’t had many responses, but here’s what they’ve said so far.