Peer reviews are wonderful to have, but it's highly likely they'll be given with more of a supportive tone, rather than an objective critique of your song. It's very important to have that feedback, but I also believe for anyone serious about songwriting, a professional critique here and there is a very good thing!

Professionals in other businesses (pick one - lawyers?) charge a consulation fee. Even doctors charge a consultation fee. Ever wonder why? Their time and their expertise is worth something and it has value. So why, when it comes to getting a professional critique of a song, would someone balk at paying a nominal 20 bucks? There's more to be gained by a professional review than just their opinion on one song. You can file the information away and apply it to future songs you write and it becomes advice that certainly pays for itself.

Get a referral from of your cowriters so you're not blindly paying someone who no one has ever heard of and who may or may not give you a worthwhile opinion. I'm impressed that in this thread alone, two real pros have chimed in, both of whom I'd gladly pay for their opinion on a song I was serious about.

http://www.julesbloeth.com
http://www.songramp.com