It all depends on your current position vs what you could achieve on aerobars. It wasn't clear from your post if you competed in a weekly TT or if you just want to see if you could go faster on a regular route.

How aggressive is your current bike? Are you riding in the drops? Is your back flat when riding?

If you aren't competing, I wouldn't bother as you won't enjoy riding in an aggressive TT position, particularly over bumpy roads. If you just want to ride with aerobars, but don't plan on getting low, you could be comfortable, but you won't be fast.