be willing to put down $20 mil minimum (i think $1mil is the lowest size you can trade in - but thats so so so small, no one will be willing to trade with you) and another massive investment in connectivity. talk directly to an investment bank like ubs, goldman sachs etc and they may give you access to their platform/liquidity pool as true fx is still otc, its still a bucket shop concept - your counterparty (ubs or whoever) will still know your position as there is little/no transparency in otc markets - so they will still run the market against you and quote against you (if your position is big enough - which it probably wont be - other wise you wouldnt be asking these questions !!) good luck
By definition inter bank is just that - trades between two banks. If you are not a bank then how can you be in that market? If you use an ECN though that is the equivalent with euro dollar 1 pip and the ability to pit in bids and offers. However banks do trade between themselves for less than a million. There are just as many different types and tiers of banks as there are different non banks. To trade on an ECN you don't need a million margin - far from.
But that still isn't inter bank - it is dealing with a bank as a single counter party. If you think they dont have the same, or more, tricks as 'retail' brokers then you are misguided. An ECN is the route to go - replicates or even betters the inter bank market
Well, between the two of us, I am the one who has experience with UBS FX. I've never had an issue with the fills. Mirrors my EBS quotes perfectly. I never stated it was INTERbank. They are but one member of the interbank otc system. I'd feel more comfortable with UBS' credit than some ECN matching engine like COES.
I can't imagine any bank in the world see's more FX flow than UBS. They certainly aren't going to fade an account who has a position of several million Euro's. And as you allude and as Refco customers can attest, counter party credit risk in OTC is of paramount importance.