I don't know what timing kit they are using, or what tyres, but I would be very suspect of any 0-something times. Even so, those times are stunning. Even if they are off by 1s they are like a dragster.
Easy, don't start timing until you are already moving
Depending on what kit is being used for the timing you can usually add at least 0.2-0.3s to the acceleration times from a standing start to get accurate times.
Production cars are regularly pulling 1.3G in brake tests now, braking distances from 60mph are edging down towards 30m.
I don't know too much about PDK or have much experience, but there's a sort of slip/rise of revs on the shifts there. Might just be breaking traction of course!
All the same, have to agree, as an exercise in pushing the envelope, it's brilliant. Of course, we shouldn't be surprised - the guts of the powertrain are what powered the GT1, which was an utterly epic and very well proven race car - but it's still amazing to see.