I own UFO afterlight (the latest one) and i have to say its rather a good game.

It has a lot of tech building, manufacturing, resource control.

I also like the way the game is designed for you to pick up and play and figure it out on the fly. The bits you don't understand at the start give you a disadvantage but become realised with time playing the game.

I don't understand the "as long as you don't expect the world" comment from the previous post, but that could be referring to the two previous titles.

The game has quite a lot of depth, is a long lasting campaign, and to me has replay value.

The combat is well done in a real time turn based way. You can slow time and pause time to help arrange your characters and terrain plays a big part in combat effectiveness. Continual day and night transitions with different environmental factors for both.

I have not played the previous versions but the last one is definitely worth it IMO