It is not about winning when you use @bellyrub or @booster. When you bid $5 and I bid $10 and nobody else participates then you get 33% upvote and I get 66% upvote. That's it. If 100 people bid each $1 then each one gets 1% upvote - and loose tons of money because the overall upvote value is just ~$35. To get a clear calculation of profit you have to take your upvote and substract 25% for curation reward. So to make a profit with a $5 bid you'll need to get a $6.25 upvote or you lost a some of it. But like I said, it is more about promoting. Be very careful using these bots or you may regret it. Overall I am very pleased with them but because I am very carefull and double check always the other bids first.