BTW double conversion UPS often have less protection than power strips. Anyone can read its specification numbers. Most do not. How many joules does that double conversion UPS claim to absorb? Notice a tiny number.
you assert that any surge seen on input of such UPS coming through AC->DC->AC transformation survives and comes out in original form??
no he is telling you read what your ups is rated for in terms of joules. A direct hit from lightning can be higher then 100000 joules.