The X-Men have had several television series: X-Men (1992-1997), X-Men: Evolution (2000-2003) and Wolverine and the X-Men (2008-2009). I have seen episodes from all them and I am going to review them here with the exception of X-Men because I only saw like three or four episodes.
X-Men: Evolution was the next series created. Unlike the previous series, here most of the X-Men were teenagers (save Prof. X, Wolverine and Storm, who acted as their mentors). I thought this is series was awesome except for one thing: the episode "Sins of the Son" had a twist ending which made the rest episode make no sense.
Wolverine and the X-Men was the most recent. The series focused on the X-Men trying to prevent Days of Future Past-like future with the help of a future version of Prof. Xavier, who somehow can telepathicly "talk" to him from the future. This series focused way too much on Wolverine and I don't like him that much. So, this series wasn't very enjoyable except for the episodes focusing on Nightcrawler (my favorite X-Man).