The best and worst X-Men volumes (pre-Marvel Now)

the BEST

X-Men (1991-2001, before New X-Men)

Uncanny X-Men (2012 - Regenesis)

X-Force (issues #1 - 115, before pre-Statix)

X-Force (2008-2010 - post Messiah Complex)

X-Men 2099

Uncanny X-Men ( issues # 281 - 393. 1991-2001)

New Mutants (2009-2012)

Exiles (2001-2007)

X-Factor (2006-2013)

the WORST

X-Statix (2002-2004)

Excalibur (2004-2005)

Generation Hope (2011-2012)

New X-Men (2001-2004)

New Mutants (2003-2004)

X-Treme X-Men (#25-46). Great series (#1-24)

Astonishing X-Men (issues # 36-68). Great series (#1-35)

X-Treme X-men (2012-2013)