I've had little or no luck myself. We do song parodies and I've posted a few here and there, and I might get 3-5 views per posting, but I've never had any great influx of views or subs from my experimentation. Most of our posts get downvoted right away and buried.
From posts I've read here in the past, Redditors usually don't go for self-promotion and will sometimes even come to your channel just to give your video a thumbs down. It seems that Reddit works better for videos from channels that are already big (unless you've got some hilarious viral-potential hit video).
I'm not saying don't try it... it could still be worth a go, depending on what you're posting and what subreddit you post to. I've just had no luck thus far.