4GB is plenty, 8GB is a nice upgrade, and 16GB is “Ill plan to take this out and install it in my next new computer in a few years”.
If the computer is performing the tasks you require of it currently then an investment in upgrading is likely not worth it. I really want an SSD for my new gaming laptop. Spending a few hundred bucks to upgrade a new computer that easily handles everything I throw at it just so I don’t have to wait a few more seconds is not really worth investing a large percentage of the computers total value in a single upgrade. I would rather wait until the computer is a year or two old and upgrade it then. It gives the component(s) I want a chance to come down in price and it gives me a chance to squeeze a few more years of relevancy out of the unit.
2011 Ext. Cab Silverado 4.3L V6 (His)
2013 Crew Cab Silverado 5.3L V8 (Hers)