First lets understand that any steemit user delegating 50/100/250 Steem Power to Steem-UA account gets 2, 4, 7 votes each week, depending on the UA score of the account, the return from the votes by @steem-ua currently looks to be far in excess of that given by delegating to a bid-bot if your user authority score is fairly decent.
There is however a concern related to post ranking. When there is low rank of the post the value of vote you get is fairly low. I have withdrawn the delegation