Depends if you want to use the top as a working surface or only to place things on.
If a working surface /recommend/, then it is easy. Just make the top the same height as your other work surfaces /or such you ca slip them under the table/.
If not, and you are OK the top being higher, then the highest is when you can open the "top" systainer and *still* easily access the contents. So about 200 mm higher than the "work surface".
E.g. me, being a high guy, I have the work surface at 930 /shared workspace/ and my highest position I accept for placing tools on is 1300 mm. Above that and it is too much *for me*.
I got to the 1300 by testing in placing the systainer in different heights and picking where it was still comfortable, but not more.
If you are 6', that may be only 1200 for you. Either way, align to -yourself-. Never align yourself to the furniture size-tuned for someone else.
