Here's my take on it (I could write a blog post on this):
what do you feel is a reasonable amount to pay for an upvote?
$0.50
What do you feel that upvote should be?
For $0.50, I'd like to see an upvote for around $1.40 - $1.60. This is about minimum when you do the math: (upvote X 0.75)/2 For a $0.50 donation, you'll be getting a $0.53 - $0.60 SBD refund not including SP. Not as attractive after doing the math. I came to the conclusion that the pay-per-play upvote bidding bots are not a "good deal", especially realizing that they receive the curation reward + your 'donation', meaning they benefit more than we do.
On the "up" side, you do receive an SP award bonus, but how much better would that SP be if you didn't have to "bribe a bot" with SBD to be awarded it. I guess it's all the same SP wherever it comes from.
And lastly do you prefer upvote bots? That carry additional services such as bank deposit with interest or just the bot voting?
If I were to use any voting bot, I would stick with Randowhale since you don't have to compete with other bidders, the upvote is almost instant, you can "bribe the bot" for the upvote within the first 15 minutes (which means you receive more of the upvote value), and rando trails adds a few extra upvotes to your post. Between all of these factors, you could actually come out pretty well. Downside is that it seems like he's always sleeping! And he's usually $1.00.
Another one I like is buildawhale, because their curation digest is awesome. Actual, live people curate among the participants and find the best posts and promote them each day with their daily digest. That is worth the price of admission right there.
@ironshield damn man this is one of the best replies ive got. Following you bro.