When you sand 0.5 to any bot this bot upvote you ) 0.8 or like this its mean you get only 1/3 of you sanding amount because 25% goes to curation reward of this bot.
When you sand your SBD to any bot you must see how much it return to you.
You can see each bot power on this website
www.steemnow.com
type that bot name and press enter and you can see like this

Then scroll up and down and see if that bot give you 1% upvote how much it give you
For Example

So,

If you give me 0.050 i give you 0.18 to 0.20 SBD vote(it is 300% Extra what you sand it to me) and 2nd beneficial thing for you My all post is helpful for you ( Because i give lot of time to steemit and i wish i create easy way to my followers they do not waste their time ) Because steemit is not easy way to make money Its depand on you( you want to earn from today or tomorrow ) then you see my blog