Best sound meter for setup?

Do you folks recommend setting up 5.1 audio by ear or sound meter. If sound meter, which one would work well at a decent price? Would a cheap Radio Shack unit work?
Check out the Rives Audio website. They have a cd that is calibrated to take into account the irregularities in frequency response of the RS SPL meter. Even with such handy devices, you will still have to fine tune by ear as it can't measure soundstage, imaging, transient response, etc... Sean
I have my probably weakest link on knowlege of room acoustics or saying simply know the teaspoon out of the ocean in that field, but seing the work of one acoustic engineer that designed the entertainment room in my cousin's house with cheapo Pierless drivers that retail arround 50...70 per 15"woofer and using simple RadioShack unit i could say Yes, you can go with it...
The Radio Shack unit works just fine....Stereophile Guide to Home Theater has recommended it many times. Get the analog model, not the digital's easier to use and make fine adjustments with, and it's cheaper to boot.