I played this on freeplay once to see what it was about. 2 bonusses, a 89% and a 91% , both lost lol.
Will never like, or play, games where you can buy a bonus and have to gamble with a chance of not getting any bonus at all. Pretty sure if they let you keep 8 spins they can spare the fiver it might give and at least you had the feeling you had a bonus.
White rabbit at least gives a bonus when you buy it.
Bonus buys are not allowed over here in Belgium btw, wise decision from the gambling commission .