I have never used Oanda so I can't speak for them. I have used FXCM and TD, I would go with FXCM for forex trading.
Anyone care to share experience w/ MBTrading specifically their EXN pay for limits" plan where you get paid to put on bids/offers on their book. On paper that seems like a good deal much like stock rebate trading 2 years ago. Unless of course their book is so thin that when you get executed there is no liquidity to get you out.
I think if we have to consider this brokers mentioned above, we should also be willing to go through their reviews to be certain if they have the qualities that we want. I'm with the one that offers me excellent services and trading condition for trading.