I think in this case you're attributing the contacts you've found to resteem bots while, in reality, those people found your post as a result of the tags you used or your position on the trending or hot page.
Tags are far more effective than resteem bots. If you want to spend that SBD then I would suggest putting it into voting bots to get your post ranking more highly on the trending page. That will get you in front of a lot more people in comparison to resteem services.
Like I said, no one follows a resteem service. There's absolutely no reason to follow one of these bots if you ever want to look at your feed again.
I love to see how responsive you are @mazzle. Always so supportive! :)
Thank you again for taking time to reply.
Yours, Piotr