I am looking into buying an airbrush and trying to figure out what would be the best option.

I am in the same situation as you are in, but after reading all the threads I decided to buy a kopykake airmaster, because I see all the big decorators like Buddy, Pinkcakebox, Sharon Z and many others use, it is a bit pricey but which good airbrush isn't, check it out at www.kopykake.com. I will find the link to the thread and post it for you, so you can research, BRB.

Here is the link to the Thread enjoy.
http://cakecentral.com/modules.php?name=Forums&file=viewtopic&p=6808143#6808143