I think his question was perhaps not between no flash hider or not, but between one option or another. In which case, I'd say for the average user, any hider is as useful as the next. Some may do better, but you won't be screwed by getting a "lesser" one.
For HD, a break might be a little more useful if it also suppresses flash, as it will direct more of the blast and sound away from the shooter (and towards the shootee). Marginally, perhaps, but something to consider if price is similar. I have no personal experience with any to recommend anything specific, though.