To be honest, I've got 2 bladders, and I'm still not a big fan of them.  Yeah, OK, "Better hydration."  That means I've got to stop more often and re-fill the darn thing.  And empty out the bladder more.  I use them on day-hikes when I know I won't make it through 2 or 3 quarts, and there's not too much danger from a ruptured bag.
OTOH, if it's anything overnight, 1 GI canteen on the pack's waist belt, and 2 Nalgenes in the pack for me.  If I go through the first quart, it's easy enough to refill on a rest break.  Never had a hard bottle break on me, or freeze (in reference to my earlier post)  I also think that it'd be a PITA to refill from a filter out on a trip (feedback here is welcome).
My advice: stay with what you like.  Try it, don't like it?  Fine, you still got a cool backpack, if you bought it as a system.