My own experience from upgrading to 16GB 2012 MBP 15":
I am a business professional too, and just bought the 2012 MBP 15". I upgraded to 16GB on my own with OWC 16GB (2x8GB) for $160. Worth every penny.
It truly amazes me what my applications use:
I run: Parallels Win-32 with Word, Outlook, Excel and a few productibity apps
Thunderbird (alone takes 400 MB Ram)
Acrobat, Chrome, Evernote...
And my machine eats 7-11 GB RAM for those applications alone.
So 8GB is not enough. You could buy a 8GB stick and keep 2GB stick to get 10GB is you want to
save money.
It is now so fast I'll put off swapping my hard drive for a SSD. Many blogs and articles will tell you that you
do not need more than 8GB is you do not do games or media/video work, but this is wrong since a many
office software need lots of memory. The virtual machine works wonderfully and allowed me from not having
to buy any software since I already owned them for Windows.
Hope this helps.