It's simple, Casumo offer a bonus structure whereby despite the deposit plus bonus based wagering requirement you are still able to withdraw your cash balance at any time in return for forfeiting any remaining bonus funds and winnings accumulated from the bonus. Written like that it still sounds like a pretty poor deal but the key detail is that whilst a bonus is in play at this casino your bets split evenly between your cash and bonus balances, therefore if you do wish to make a withdrawal you should still have a sizable proportion of your winnings available in your cash balance.
Still, a 25% bonus isn't nearly as attractive as the initial 200% match or even the 2nd and 3rd deposit 50% match bonuses. What really made me choose to accept this deal is the lack of restrictions or dodgy terms imposed on bonus play this casino - there are no big lists of restricted slots, or games with stupidly high additional wagering requirements. Everything is kept very fair and simple, which is becoming almost impossibly rare in today's market.
On top of the very fair bonus terms, Casumo have great support and super fast withdrawals, making any promotion they offer all the more attractive. They offer this bonus twice too, as it is also available on your 5th deposit but as the terms are identical to this bonus it seems pointless reviewing both, therefore I will just say right now I love Casumo's entire welcome package and definitely think this is a casino to watch in the future.