A few on chat have described how they use the neighbour method for Roulette with an initial bonus and then grind on slots to complete the WR if win. I have been doing the EV calcs and wouldn't mind someone checking them for me.
Assume £50 100% bonus, HE = 5%, bet £20 chunks on 0 and four neighbouring numbers.
If Win: £20 x 35 - 75 (loss on grinding) = £625
If Lose: -£50
EV = (5/37)*625 + (32/37)*-50 = 84.5 - 49.13 = £35.37, a loss of £15!
Am I missing something??