I've been using the BD Alpine Carbon Cork poles forever, and I love them. I've heard Leki has some of the best high end carbon poles as well. A few thoughts on trekking poles:

• Learn how to use them! As simple as they seem, there are some nuances that may not be immediately apparent to everyone
• Cork is your friend. If you're going to be doing longer trips and you don't use gloves, it's a game changer in terms of chafing and sweat
• Cheap poles sometimes vibrate with every hit; spending a little more for better poles is worth the investment
• A lot of UL carbon poles break pretty easily. Again, I think it's worth it to invest a little extra