I've been happy with fixed length poles. Two of them were second hand, and started life as telescoping poles that broke (and then ended up as trash). I then riveted them in place to make fixed poles. I've had luck getting broken poles from riggers.
One of my second hand poles had really cool
racing boat style pole ends. With a bell housing on the
mast and a sort of pin on the pole that looks like a spacecraft docking mechanism. It was neat because it would click home all by itself, without having to open jaws or anything like that.
I read in one of the old cruising books about extending the track on the
mast that the pole traveler car slides on. So I did that, so that I could slide the pole up the mast and clip the other end of the pole to the base of the mast. I feel this is super duper, since one person can then set the pole really quickly and easily. Just have all the lines cleated on the right lengths, then pull down the traveler and the pole naturally swings out into the set position. Pretty cool. Otherwise setting the pole for me has an awkward stage where it's not completely constrained and wants to swing around.
Also, poles do not have to just be for light air. I used them quite a bit in heavy air, it keeps the jib filled and from pumping the forestay if the boat slews around from the waves.