TL;DR: 7 three-breasted ladies out of 10
++ quests and companions
+ good monsters
+ graphics
-/+ music
-- combat
- character development system
- animation
- GUI
-- navigation

Probably most enjoyable part of this game is quests. There're are many, you always have something to do, very often you can solve problem in peacefully and there's almost no filler quests. They are not geniusly written, but more than decent.
Companions' are pretty good too, they are diverse bunch and each gives you bonus to certain skill. Their banter is not excessive, so it's always interesting to hear something from them. You can romance some of them. Again, it's not Dragon Age, but enjoyable nevertheless.
There's karma and faction and NPC relationship system, not unlike in Fallout: New Vegas, although it's not as influential.

Game have distinct air to it. Overall setting is post-apocaliptic (shackled cities, mostly low-tech society, hi-tech ruins, a lot of lost knowledge) with pinch of cyberpunk (planet is ruled by corporations, lots of social problems).

Combat is slasher-y, and, to be honest, kinda dull, despite all sparkles and slo-mo critical hits. It's somewhat fixed by inventively designed monsters.
Same goes for character development system, new skills usually give you +10-20% to evade chance or something like that.

Overall visuals are nice. Mars in this game looks like hot desert (because of terraforming perhaps?), but still with thin atmosphere (sharp shadows). On the other hand, animation look poor. It's okey-ish in combat, but in dialogs it's just not good.
GUI could be better though, it's not as good looking and not always intuitive.

Navigation is terrible, especially in cities, where you often find yourself in the middle of twisty little passages, all alike.

Music is ok, there are good themes, but repetetive. So maybe find a looped version of Metallic Monks (or whatever your favourite theme from Fallout series) on youtube:)

Despite all those problems, I'm enjoying this game. Maybe buy it on sale and give it a try?