Why spend so much money for a product that does not do anythng useful?
That UPS already has the same protector circuit inside. What does that 'incoming' protector do when the equivalent circuit is already connected to the same UPS power cord - just inside the UPS?
What does the outgoing UPS do? UPS manufacturers quietly recommend no power strips on their output. The reason why was already posted with numbers. Output from one 120 volt UPS is 200 volts square waves with a spike of up to 270 volts. That is ideal power for all electronics because electronics are so robust. Anything that second power strip might do is already done better inside every appliance.
And finally, if those power strips are recommended, then you can post manufacturer spec numbers for why each is useful. Either you can post those numbers, or your recommendation comes from bogus assumptions. Is based in hearsay. What numbers from each Belkin protector accomplish what you have recommended? I say so knowing you will not post. Because Belkin does not claim to do what you are recommending. And because a power strip on the UPS output might, in some rare cases, be harmful to the UPS when in battery backup mode.
Where are numbers from Belkin that justify your recommendation?