I liked that to receive this bonus you could deposit as little as 10€ and so I did. I received 25€ bonus and with 35€ I had to wager 1000€. Then I went to play 300 Shields slot because it can produce very nice winnings. I don't know why but the game was in an awful mode, I couldn't get winnings higher than my bets, which were the minimum. Within the first 100 spins I couldn't get any free spins round and lost 10€. I played another round of 100 spins and nothing changed and when my balance was down to 14€ I decided to use it on some other game. My decision was Big Break slot because I hadn't tried it before. I think this game is decent for wagering requirements as it gives winnings on almost every spin, small ones, but still. I played with 0.15€ bets and it took me around 200 spins to get a bonus round. I got about 5 Surf's up bonus rounds one after another. The smallest one gave me 4 x bet winnings but biggest one - 20 x bet. At some point I also got 15 free spins but they paid only 10 x bet win. Overall I played for about an hour, since I kept playing with small bets, my winnings were small and eventually I lost all balance.
I think this bonus is really good because of the wagering requirements it has and the bonus amount I consider to be very generous for second deposit bonus. I still think they should improve their game selection so that there would be more slot games, especially more Microgaming slots. I've spoken a few times already with live chat and they are very accurate and they can explain all questions you might have so I think this bonus is recommendable.