Ya, I agree, 180 is a bit too long, but only if you do alot of powder and back country then it might work out, You wont have any problems skiing park with them, but it wont help you. I am 6 feet and ride 173's. I think they are great, and I ride powder in them like anything else. I used 163's for a while in the park, but they were too short for landing switch. I didnt notice a difference spinning so I liek teh 173 best. I thin ka good lenght for anyone 5'10 and taller is 170-178. But thats just me, everyone has their own opinions. Try demoing skis and find out what you like.
I don't mean to toot my own horn, but 'Beep Beep!'