out of sheer curiosity, why would you recommend a mac when most every trading software you use and others use target Windows? I get why some drive old timers, for the sheer beauty of the car and the craftsmanship. But then a trading computer is supposed to get work done, not to look beautiful or have aluminum rims and edges. I just wonder what attracts you so to a mac when most of the stuff you use is Windows based. By your own admission you do not use the mac to show off or feel better about yourself. Honest question...
Definitely. Basically any modern piece of hardware will handle almost any competent trading platform.
A solid setup IMO, rather than a mini+ext display is the 27" imac retina as the former is more powerful, but the mini should work fine. Alternatively you could just run a windows box for your trading platform as well (but it's pretty easy to flip back and forth between VMs and native).