My comment is for @shares as I support and used this service.

The main advantage of using @shares you bid to win not to lose. If the bid is full you will be refunded right away. And if accepted you will gain 10% gain or more.

If the round is full, you can try again after the 2.4 hrs. The trick is bid early to get in.

Other bot will continue to accept even there is no return of investment. They have investors or leased SP to pay, so they will accept all bids. Due your diligence before voting.