I think this skill is a must. Even with 1 point in it you can get nice boost to your much needed armor rating. Giving up the wand is sometimes well worth it, and actually you can get almost as much int without wand anyway. Only downside is after your Talak rounds are over you do a lot less damage per round when you are only able to hit with your staff.
With 1 point we are talking about 350-500 more armor, at 5/5 it's 700-900.
The tough choice is whether give up wands completely or have them both.
When taking both you have more options, but can't max either one out. If you know your matchups it's definately better go against them with a bit weaker but more suitable build than fighting everything with maxed out build which is weak against some.
Currently I'm testing full staff focus build, but haven't given up wands completely yet. So far it's looking good, there are some fights I have been hoping to have wand (IP), but most of the time I'm happy to have all that extra armor.
Still need to get my Asps to get most out of it, but Crook has been working great, and I don't believe I'll abandon that stick either any time soon.