Avatar uses Lightspeed as well. Or at least they did. Don't know if the Schonfeld/Lightspeed merger changed any of that.
Good place, good vibe. Owners "appear" to be ok, but haven't traded with them to verify their honesty. They claim no volume or commitments, so I don't know how that translates into the rates they will give you.
If your decision is about platform, then look to the Anvil, as it has been highly praised here. Blackwood has been known to been know to be a little buggy.
I know, not much help. Good Luck, tho.