I've had a mini account with them for a few days. During this time I haven't encountered any problems, I was also satisfied with fast execution of (few) quick trades with a minimum (1-2 pips) or no slippage. But I've heard some rumour, that it is risky to play with them, so keep searching on forums and find out Yourself.
I used them a few years ago and have alot slippage in fast times. I use CMC now and if there is splippage they tell you and have 5 seconds to accept it or not . Things might of changed though .