I am very impressed with these, and with the service (only ordered them 2 days ago and they arrived today!). I buy a lot of slippers, and I've found that none last more than a few months (even the expensive sheepskin ones). I wear them about 5hrs/day and have managed to wear out Just Sheepskin/M&S/Next slippers to name but a few.
Granted these are new, but considering the weak points of the others these are promising because they have a hard sole that can be worn outdoors (for short trips to the bin, etc.), they are inexpensive (I paid £6.83) and don't have a thickly cushioned sole which is prone to rupture/gradual flattening (which makes them v.uncomfortable). They are not overcomplicated so there is less to go wrong as far as I can see. Warm, stylish in their simplicity, and comfy.
If you are looking for bouncy shock-absorbing slippers these are not for you as the sole is not heavily cushioned, but the advantage is that you don't slide about in them. They are the perfect fit for me as a size 7 with wide feet, so I guess if you have narrow feet there could be an issue with fit.
The depth of the slipper is also perfect for me - I haven't had the same problem as the reviewer who found them uncomfortable due to rubbing at the top of the foot.
I will update this review a few months down the line once I have put them through their paces, but so far these are the perfect slipper for me. I'm going to order another pair today.