I have now done the next round of 100 spins on lowest betsize and the winner is Rainbow Gold!!!
I now done the 4th round of 7 slots and the stats:
The best slot this round was:
Rainbow Gold, used 20€, returned 44,25€, RTP: 221,25%
The worst slot this round was:
Black Bull, used 20€, returned 6,65€, RTP: 33,25%
Profit/Loss this round: 17,97€ Loss
Total Profit/Loss: 266,28€ Loss