I have the Samsung Series 7 Slate 128 GB & SSD 4 GB RAM. It has been discontinued, but thoroughly compatible w/ Windows 8. It is the same tablet distributed at the BUILD 2011 event. I find it to be a battery hog, buy otherwise a very enjoyable device. I've thought of upgrading to a 256 GB SSD, but there are mixed results about opening the device.
Been looking at the Lenovo Yoga, especially if I can get one w/ 256 GB SSD & 8 GB RAM. The standard is 128 GB SSD & 4 GB RAM at $1K. Also it has USB3.