My wallet is full of 0.001 transactions with messages about resteeming services.
I've used all the ones I posted above and other than @resteembot that only charges 0.0-- per post, none of them have generated significant views, upvotes or revenue.
But for generating upvotes @randowhale and @minnowbooster upvote value, is more than the 1 SBD they charge so you get more back than you paid out.