Marketing with rendering

[lovethepirk]

Hi all, thanks in advance....

I run a version of NX CAD software that has rendering capabilities, but I have not tapped into them.  As I began to study rendering I learned of this software which I do not have yet.

I would like to create some renderings of my product(s) and was wondering if such photos that I find mind blowing are renderings or not:
http://www.chevrolet.com/corvette-z06-supercar/exterior-pictures.html

1) Are some of these Corvette pics renderings that could be achieved with keyshot?  I ask b/c that's how I found this software, thinking the corvette pics looks too cool if there is such a thing....

2) With diligent and 3-4 hour practice sessions, how long does it take to really begin to produce some realistic and impressive results?

Thank you.