Does your trading app have DOM?
There's no "DOM" for spot forex. And no volume. The only DOM and volume that exists is the broker's own DOM and volume, and that's garbage.
If I opened a live account then it would be an ECN broker which - if I understood correctly - basically transfers my trade into the real market.
You
don't understand correctly (which is why I'm replying to you in such detail).
You believe what most retail spot forex traders believe: that the "magic" letters "ECN" make the whole situation different, and that if you use an "ECN broker" you won't be trading against them.
It isn't necessarily true.
All ECN means is literally what it stands for (electronic communication network) and virtually all brokers have that. They use it to imply that they're passing on all trades in an automated way to their own liquidity providers, to make people in your position think to themselves "Oh well, that's ok, then - they're not really holding the other side of my trades".
The reality is that some do and some don't, and
you have no reliable way of knowing which is which. They tell lies.
Another "tricky marketing expression" to beware of is "no dealing desk". It's used for a similar purpose.
There are endless regulators' rulings, internationally, that demonstrate exactly how little it means.
Don't be fooled.
It's a shark-infested marketplace, and you're the prey.
Especially if you deal with "exotics".
After having scrutinized many brokers I think IC Marekts would be a good choice.
I have no experience of them.
The little second-hand information I've heard about them hasn't been bad at all. I've heard a couple of good things, and I've heard
no allegations that they're outright scammers or crooks, and that in itself may suggest that they're not too terrible.
More than that I can't say.
I really don't want any market maker to be in possession of my funds. I'd rather have a pip more spread than having a market maker broker. An additional pip for spread does no harm as I am not intending to scalp.
I hear you, and you're right.
But you don't have
quite enough funds for that, really. Soon, maybe?
The best you can hope to do, for now, is use a "good counterparty" who has little incentive to steal your funds.
For the majors you can find plenty of information, but not so for the more exotics
There are reasons for that, hello?
roughly what lot size do you have to reckon with slippage and by what amount?
I have no idea. I wouldn't touch any of the instruments you're asking about with a barge-pole, sorry.
On EUR/USD I'd want and expect a spread of about 0.9 pips, and on Cable about 1.3 pips, during RTH, from a "no commission, spread only" broker.