Voted for
- No.
Bidbots are not profitable in most cases. You will lose money, if you use them.
There are paid upvote bots (not bidbots), which guarantees a specific amount of return. For example Smartsteem nowadays have a fixed 10% ROI (5% BONUS for limited time). MinnowBooster usually have 6% ROI for normal users, and 12% for whitelisted users. Sometimes they increase it. For example in the December of 2018. They increased it to 8% for normal users, and 16% for whitelisted users.
There are also free upvote bots. For example the Minnow Support Project have a free upvote bot on the Peace, Abundance, Liberty Discord channel.
Steem Monsters also have a free upvote bot on their Discord channel.