I'm actually looking for a new aluminum seat post myself (also for a caad9), but don't want to go Thomson either because I've seen way too many part failure posts online lately. They seem like a boutique machine shop that happens to make a few specialty cycling products. I know the seat posts have a good reputation overall and a huge fan base, but I'm really not in a hurry to join the club. I recently picked up a Deda zero100 SC stem and Newton shallow-drop handlebar in their DMP (Dark Metal Polish) color. I'm trying to find a matching zero100 seat post, but they are discontinued in that color and I can't find one anywhere. I wish there were more non-carbon options out there.
FWIW, my 3T Palladio seat post is the best post I've ever owned. It's genius. I wish 3T would make this in a silver aluminum color.