What's interesting is this is a 'mobile workstation' but doesn't have HP's docking port connector on it. Fail! Their thunderbolt dock is far more expensive than the traditional docks.
I think the only real benefit you're getting of buying this device is the fact it can us ECC RAM which I doubt most users here need on a mobile device.
from notebookcheck:
The ZBook Studio G3 is a small mystery to us. HP delivers a great product in some respects, while it disappoints in other categories. Sadly, overall, our impression of the ambitious workstation is negative. This is mainly a result of the emissions as well as the battery runtimes. The surfaces reach alarmingly high temperatures that can cause burns, even with normal workloads. The fan behavior is also very annoying, because both fans act independently, get very loud and pulsate heavily. The practical runtimes of less than four hours are also hard to justify for a device that is actually pretty mobile. Otherwise, there are just small issues, like the lack of a SmartCard reader or the missing WWAN module.
Wouldn't feel too bad if you miss out on this deal.