i came across these mattresses being sold (in Overstock.com, i think), and i'm wondering if they're any good? The reviews were decent, but the price is so good i imagine they can't be great in the end...Any comments? Thank you!

(i'm interested in any mattress that has little to no motion transfer, as i just can't tolerate my partner's movement!)

I'd be very careful buying a mattress from Overstock, since you can't return it if you don't like it.  If you're still leaning towards ordering a MF mattress check out Overnight Mattress at http://www.overnightmattress.com Prices are very reasonable. They ship free and if you want to return it they will pay return shipping. Hard to beat that. One of our regulars: Jimsocal, bought one recently and seemed to like it, although he found the 2" MF side a bit too soft for his taste and flipped it over. All foam mattresses have minimal motion transfer.