Both games have similarities and both games are fall under trilogies so which is better of 2?
I personally found Bioshock to be worst FPS trilogy (well until wolfenstein 3 release) as original bioshock was incredibly overrated and poor mans system shock 2 and infinite imo is one of the worst AAA FPS of all time. so Metro by default is better.
Metro have flaws and problems like having bad AI and not so good shooting but its story and atmosphere is far above. all 3 Metro games have been fantastic and having pros and cons among them.
so friends lets vote and discuss which is better of 2?