It works fine, but you're beholden to the Reddit overlords, you don't have enough control, and if someone decides that your subreddit no longer fits with Reddit's brand, or that old posts should be purged, etc that information is lost. Then there's the whole old vs new reddit, its complete inaccessibility from web (for which Google will probably punish them at some point) in favor of the app, etc.

So yeah, it works, but with some big caveats.