I've played at Simon Says and at Slotocash. I took a free play, and had a pretty good run at Simon Says before bottoming out. I played at Slotocash because they seem to have a good reputation here among certain players, and although I have not had a withdrawal, I have been happy with the responses and response time from CS.
They offer no cheques, my preferred method of withdrawal since I deposit with a prepaid credit card, and I had difficulties establishing a Moneybookers account, which I tried to open in order to make a small deposit to claim winnings, since they had to pay back to an ewallet.
Moneybookers made a small withdrawal from my credit card, but I had to report it in euros, and it shows as CDN dollars on my cc statement. I get no paper statement, and while I have the option to arrange to deposit from my bank account, the whole reason I have a prepaid CC is to AVOID having my bank account available for gambling...I can be impulsive, and like to put my own brakes in place. Anyway, I gambled back what was a significant (for me) win due to lack of a means of withdrawing, but I enjoy the Rival games, and found their CS most helpful.
BTW, if you take a bonus, read the terms and conditions carefully. And you have to keep contacting support to see if you have met WR yet.