I did find the homeschoolreviews website to be helpful but dd really wants another kid's perspective, especially since the ones we like are so expensive! I don't want to spend a ton of $ and find ourselves stuck with something she hates.
I have done both OM and Calvert. We are doing Calvert this year for grades 3 and 5. My almost 11 year old likes it for the most part. It is a pretty hefty work load (4-6 hours a day) but its complete and a good, challenging . Next year we plan on switching a few things up, because Peyton likes that.
Calvert and OM are about as different as one can get i think.