I'd read a few reviews of this EDZ item and thought that it seemed quite good, however the RRP is £50 which put it out of my price range..
After a few months scouring Ebay I managed to obtain one for the sum of £15 - which is much more to my liking..

The jacket is carried in its own bag and it is a small bag. My immediate thought was something that packed down this small was not going to keep me warm.
This impression was re-enforced after unpacking it. The material is thin and light weight. The garment has elasticated cuffs and bottom and a furry collar with a short angled zip to allow you to get it on and off.

As today was a bit cooler than of late I thought that it would be an ideal opportunity to try it out. I wore it over my t-shirt and under a perforated jacket and set off, convinced I'd have to return home to get another layer..

To my surprise, after 150 miles of mixed motorway, A and B road riding the top did an excellent job of keeping the wind out and body heat in.
The other thing that impressed me (and it'll be interesting to see how it does on a hotter day) was that I didn't get a sweaty back from my back protector something that has happened when I've worn other 'performance' fabrics.
The old leather jacket slide off much easier so I could see the benefit of using this or something similar if you wear one piece leathers.

In conclusion I was impressed, especially after seeing how thin and lightweight it was.
I've rated this item 8 comfort and might well increase that if it performs as well in hotter/colder weather.

I still wouldn't spend £50 on one, although I've seen them for £35 ish which is more in the bracket I'd put it, if you paid that I'd think you'd get VFM.

I've got one - it was free with a subscription to Bike magazine (never seen anything else since so useful as a sub offer, unfortunately). It's especially useful to wear under summer stuff (eg unlined leathers with stretch panels/perforations) when you set out in the nippy dawn. Then you can roll it up in its little bag and stuff it under your seat for the roasting ride home! The only minus point is that it makes me look like I am wearing a bin bag when I take my jacket off - even the XS is huge on me!