My husband swears these are the warmest slippers he's ever worn. The "suede" exterior feels substantial and the wool inside is wonderfully plush; they seem as though they'll last a long, long time. But comparison to similar booties offered at other outdoors stores demonstrated they were not really the great bargain I believed them to be. We're still happy!
Note: being a half size, he rounded half a size up as recommended, but ended up returning them and rounding the half size DOWN.