Imho UMD is good in higher level or with good stat and with a +5 UMD item (2500gp).
e.g. with level 8 (11 rank) and with 16 cha your UMD is 19 = 11 + 3 + 5
So you should use any wands without roll.
e.g. with level 8 (11 rank) and with 16 cha your UMD is 19 = 11 + 3 + 5
So you should use any wands without roll.