I use Schwab's StreetSmart Edge, TOS to use their custom scans and free access to BookMap, and Tasty to monitor the most active options. This takes 7 screens on 3 CPUs. I execute all my trades through Schwab and get pretty impressive fills - I swear I often get fills that are better than the NBBO I'm staring at in Level 2. Used to use IBKR, but getting through to their customer service was exhausting.