Get(SystemPlatform) = 4
Better and simpler. It's also 13 as is the Hide abiity. Clean and simple.
SystemVersion is a real mess...
I would definitely use get(SystemPlatform) instead of SystemVersion ... when your goal is to detect that the user is coming i via WebDirect. Especially since you does not get one coherent answer to you question with SystemVersion. With get(SystemPlatform) you will get 4 when it is WebDirect.
With Get(SystemVersion) web direct will give you a lot of different answers that you will have to handle individually ...
What I am trying to say is that the answer you have marked as the right answer is wrong and that you should mark Jack Rodgers answer as the correct one.