The UPS is a better deal off the better insurance alone. Ignoring the additional feature, you get twice the insurance for the same price.

There really is no downside. The batteries are replaceable. There is a door to do it so even doing so won’t void the warranty or lock you out of support (unless you attempt another way of doing so).

Only thing I can’t confirm is the UPS surge protection power rating (as in how much power above the standard current you are protected/insured against).

Checkmk

Why not a purple? It’s even advertised for exactly this use case