i have 2 pairs of the solar shoes (i think that the style name)...they look like mary jane style shoes (obviously flat) and a pair of boots w/ furr on the inside. those suckers are soooo warm...and for me, thats amazing, as i am always cold. i got those on sale for 80$... the shoes are ok. the negative heel in general takes a little getting used to, but ive been wearing high heels all the time for the past decade! haha. but now i have nerve damage in my feet (from other things) and my balance is off, so these helped me "ground" myself when im off kilter.
i have other shoes as comfy (and cuter) from payless.
but, i think they are constructed well, and will last. plus, you cant beat the company. make sure you investigate about pricing...ive seen quite a range. zappos.com also has alot of reviews. thats where i got my boots from, offseason.
oh, and i think i got the solar shoes for 89$ on sale, from gaiam.com. a couple years ago.