Remember that trading with ECNs still has its drawbacks, take a look at the link below where someone had 250 pips slippage on EURCAD with
ODL Securites on
Currenex - it looks like ECN brokers also employ downnright fraudulent practices too!
http://www.forexfactory.com/showthread.php?t=24672
I suppose the best thing would be if would could trade forex from a centralised exchange, like is done with the CME. I now believe that the proponents aguing against this are all the institutions that make money from this type of slippage. It makes sense. With today's technology, there is absolutely no reason why the forex market cannot be run from a centralised exchange.