For those of you with a Pro3 thinking about upgrading, imo, don't. Don't get me wrong, the SP4 is a nice machine and if I didn't have an SP3 it would be a no-brainer but there just isn't enough to justify the crazy pricing. Yes Windows Hello is a nice feature that worked flawlessly for me but the performance increase and slightly larger screen and lighter weight was hardly noticeable. Microsoft wants $2000 CDN after trade-in for an upgrade from an i7/512/8 to an i7/512/16. I don't think I would spend $200 for the upgrade never mind $2000. Having returned the Pro4 I can honestly say I haven't missed it for a second.