Should I go OEM or A/M air conditioning?????

[SS1156]

I need some help here guys and gals. I am looking at purchasing a 2nd Gen Camaro and I definately want air conditioning in the car. I have narrowed it down to about 4 different cars. Some of the cars have all the correct a/c components and some do not. I know there are companies out there that can retro-fit a complete system that works great. My question is should I look for a car with the OEM working a/c or should I get the car that would need the complete aftermarket a/c system installed? Of course I would price the non a/c car cheaper to offset the price of having to install a/c in the car. Do the aftermarket a/c systems cool better because they are designed to work with the 134a vs retro-fitting an r12 system to 134a? I do like the clean firewall install of the aftermarket a/c vs that big box that the oem uses. Can you take a factory a/c car and pull out all that stuff and go with the a/m a/c? Sorry for all my questions but I just like to get educated before dumping a lot of my very hard earned money in to something. I like to ask questions from the people who are actually involved in doing it. Magazines are good reading but sometimes reality is left out. I really do appreciate everyones input.