I have personally tested all the "currently" released laptops with win 8. if you want a screen that DOES NOT MOVE or flop try the acer V5. I personally bought one of those and it is the full win8 version and I have Vis Studio 12 installed. I tested every machine I could for that Flop and there may be others that do not flop, but I can personally assure you the acer v5 does not. If you buy it you will have to change the setting on the touch pad. The default settings are off and make it hard to use. The touch screen is nice really nice. Sleek machine, your arms can reach the screen easy.
I like the Samsung 13.3" Series 9 laptop at 2.6 pounds weight. But it has to have Win 7 and a regular screen because if a laptop is held and used like a tablet then the keyboard is just in the way.
I would be okay with a version of the Series 9 that rotates the screen and then snaps it into place over the keyboard with the screen facing up for tablet use. That could have Win 8 but it must not weigh more than 2.6 pounds weight with a 13.3" screen.
These convertible laptops that weigh 3.5 pounds are funny.
The other form factor is the Samsung ATIV 500T and 700T. They simply detach from the keyboard for use as a tablet. The weight is 1.6 pounds and the screen size is 11.6".