Tried my hand at using the upvote bots first time today. sent a massive 0.35 SBD to 4 different bots. 2 were profitable, one about break even and one came out about -10 ROI. So in total I came out with a small profit in SBD and also gained some Steem Power.
I Certainly think I'll use them more in the future whenever I have a post that I put in a bit more time and effort into.