It’s a great machine for the month I’ve owned it. The PCI Express SSD means it’s easier to just use the hibernate rather than the sleep mode. Read writes are hard to explain, just think really really fast compared to anything previously out there.
The slice battery is useful, but might be overkill if you only need 6 hours. I don’t even use mine. It will be a nice to have later on when the internal starts to go down with age. The 256GB SSD is nice, the jump to 512 is overpriced to say the least.