there are two good reasons to get telescoping poles:
1. you can use a longer pole for more leverage for hiking (like xc poles) and a shorter pole for turns on the way down.
2. you can set one pole longer than the other for sidehills. You can switch hands at switchbacks to avoid resizing both your poles. I've never done this, and never seen it done. I usually have some grip tape on the upper shafts of my touring poles and just hold the pole by the tape when sidehilling.
Basically, the major drawback of telescoping poles is unintended collapse. Most of the twist to collapse poles tend to do this. The twist to collapse poles basically have a jam nut and the shaft that expands when the lower shaft is twisted.
Black Diamond flicklock works pretty well at avoiding collapse. Flick lock is more of a cam that clamps around the lower shaft to prevent collapse.
Life-Link makes a pretty decent pole, not a whole ton of adjustment range, but enough.
2 piece vs 3 piece:
2 piece: fewer joints to collapse/break
3 piece: stow away better.
basically, unless you plan to carry the poles inside your pack and collapsed length is a necessity, go with a two piece.
Avoid probe poles. They are not a replacement for a dedicated avalanche probe.
Oh yeah, avoid komperdell, they suck. My wife picked up a pair of their 3section poles for snowshoeing up to snowboard down and i have spent some miserable time trying to extend/collapse/lock/unlock those bastards.
"They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety."
Ben Franklin
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