Just receiving the new sputnik, oh hell no, the Ubuntu install was so broken. The benefit of shipping it with Linux is at least they made a decent attempt to work with Linux. Why an attempt? See first sputnik laptop.
No but I would at least have more confidence in the driver support for the hardware included.
In this day and age, I don't see how any (profit-based) company would provide a clean and trustworthy install.
If Microsoft forced them to.
Regardless of whether you trust the pre-installed software, it would assure that the hardware and firmware are compatible with Linux. Whether they rely on proprietary drivers is another question though.