I see some good reviews for it on steam store page then some negative (of course). The negatives worry me a little because they say that some mission are just terrible (I believe the escort missions and only allow you to pick maybe one person while others are predetermined), had some people pissed about enemy spawning (enemies would spawn right next to them and kill their squad member in same turn), and a few other little things like items/gear doesn't drop that often (some were saying you have to do 4+ missions before getting anything of value for your squad).
I almost fell into that trap where I decide after clearing all enemies on screen to explore the map, spreading all my units out only to find out I triggered more of the mission where the Locust invaded again.. I managed to survive unscathed but it shocked me. Not all the missions are going to be 10/10 however they are quite good all round. For me, I am no fan of time limits in games and I just accept them now rather then complain about them later so to with escort missions, I just accept them as variety rather than a bad design choice.
I run a GTX1080 and I haven't had the game crash once.. yet so I cannot say if that's an issue or if some people are just extremely unlucky.