Just started playing it a few days ago. It's okay. Significantly more... granular than XCOM: EU/W, which is nice, but I can't say I'm fond of the visuals or the lack of customization options. Also, facing and cover is incredibly finicky; the latter in particular seems to be nigh-useless, since it seems to only work on incredibly specific angles.
Interceptor minigame is an odd beast, the default AI is a lot better at it than I am, since I cannot for the life of me get Sidewinder missiles to hit with anything like consistency
Think I'd prefer a Steambirds-esque simultaneous turns setup to RTwP.
All told, I like how much stuff to do there is in the game, and the strategic layer is certainly more interesting than XCOM's (Firaxis, take note!), but the combat seems irritatingly easy to mess up, and as I said before, the visuals are very meh.