Do not use Ties Technologies (tiesrack.com and tiestech.io) for anything serious. I used them for the past six months for small trades and it was okay. When I deposited a larger amount and traded more, my account was flagged, my withdrawals were delayed, and I was asked to explain my trading. They treat active traders like criminals.
Pros: Transparent fees|Fast deposits|Clean UI
Cons: No phone support on weekends|Limited cryptocurrency options