just make sure you get one from a good popular company. i shopped around alot for one. replacements parts availability and stuff is always a good feature.
i got a velbon dry carbon one... here is the link to mine... i have the 540 one...
http://www.velbon-tripod.com/sherpa_pro01.htm
anwyays, make sure you look at how much your tripod can carry. i had to make sure it would handle my 10d, "L" series lens, and 550ex flash... cause it can get heavy. i feel like the twist tighten legs are more safe and durable then the clips ones.
i use my tripod as a mono pod everyonce in a while. hahaha... kidna weird but it works. been hiking, traveling, and a tripod that is light is worth the money for me. look at portability if you need it..
try going to calumet photo cause they have alot of tripods there. also you can rent them if you want to try them out. it is good to try them out for a day. i rented lenses there before i bought them and it was very helpful... i didn't buy my stuff there but they got good stock and stuff. kinda like a best buy where you get to play with the stuff...
i didn't get an expensive pan head, i got the velbon PHD-41Q, and it is very easy to maneuver. has a quick release and stil sit stable with the quick release on the bottom, well not with a heavy lens...
haven't had any problems with my velbon, so i woudl totally recommend it...