Anyone use ATC or have any recommendations for ECN brokers?(I'm in US)

I’ve looked in a lot of places so far trying to find a good ECN broker that takes members in the US. My starting amount is going to be 4-5k.

I need one that is good for scalping too, but haven’t had any luck so far… there was a mention of one ECN in that thread with all the overseas brokers which still take US members I think it was Finfx, but I’ve seen a few reports of connection issues which seems bad. Is anyone actually using them for scalping and not having problems?

I found one based in the US - ATC brokers, but they seem way too clean especially on FPA, which makes it seem quite odd. Has anyone actually used ATC brokers before?

Thank you all in advance.