The NI cards are integrated into switch executive such that you can easily set up your routes through pictures of the switches. I'm guessing, I haven't used them, that the Pickering ones are more manually entering in the routes without the pictures. Basically you have to know the route names and such.
I think if you just get the eval and play around with it you can see how easy/hard it will be for you. It is trivial from TestStand once you have it set up in Switch Executive.
Hope this helps,
