EDIT: I thought the GG poles were non collapsible. They are (though not very, which is a problem). But I leave the below as evidence that there is often a lot of bad advice on the internet :p
One thing to consider.. If you get non collapsible you will be pretty much committed to using them for the entire 7000+ miles. You won't be putting them on your pack and they'll be harder to mail. Unless you leave them at home…
Another thing… just buy whatever. if you're like most people you won't care much at all about your gear after a few hundred miles.
do you have any experience or have you been on trails or to stores and formulated some opinions on what you like?
My opinion:
– I wouldn't go with non collapsible poles because some hikers develop carpal tunnel from poles and want to put them on their packs for a while to let their wrists recover. This happened to me.
– After 4 pairs of them, I'd ignore the MSR carbon poles
– I like carbon because i feel that they really do "dampen" each strike.
– Sooooo… I bought BD Carbon poles for my future hikes (including the cdt). I like most everything about them but wouldn't buy cork grips again as i think that the durability is poor.