Hopefully some of the pros out there can help me with this question. I am trying to figure out what the differences are between power brad and finish nailers are? I know the guages of the nails are different, usually 18 for brads and 15/16 for finish nails. Other than that, what is up? I noticed at Lowe's the brad nailers are half the price of finish nailers. I'm looking for a good tool for doing trim work around the house and whatever little carpentry projects come up in the future.

Any input would be greatly appreciated!
Chris