@awwsmm, thanks for the suggestion. RoA works well, though exhaust still fits my play style better than Flash. I'm going to have to wait until I have more IP to try the seals though. Early Glacial Shroud is a good idea, but more situational, since it's only really worthwhile if you're going to be building a frozen heart.

Warmog's then really late resistances is bad.

I'll vote this up because I think this is a generally good build. I have some problems though; the CD seals are not so great on him, since you lack mana so much in the beginning it would be a safe investment for MP regen seals (either per lvl or flat) they are much more useful imo because all the CD combined is still not that much. Another thing warmongs is a bad item, it is so expensive and unless bought extreemly early is not worth the money, sure it gives cho even more health it does like nothing else. The HP regen is useless cause of all your HP. I would reccomend replacing it for a Rod of Ages this will give you more early mana, additionally how bout grabing a Glacial Shroud earlier for mana, armor, and some usefull early CD reduction. I am not sure bout Exhaust on Cho', I prefer the spell of physical DPS not tanky AP champions like Cho'. Instead I would reccomend using Ghost and Flash but that is just my personal preference.