I broke down and bought the one from Lowe's the other night ($29.99). More out of curiosity than anything.
I should have done it years ago! I'm finding different moisture levels pretty interesting. Two pieces of maple cut at the same time (7 years ago, 5/4"), but stored different places read 8.4% and 14.1%. I have a couple boards on the way that I want to try it on and also some beaver chewed up dogwood that I'm wanting to check out when I get time this week.