Salesmen love the 25 Year Performance Warranty because they can boast how their panels are covered for 25 years.

This is taken directly from the 833 Warranty Spec:

“Limited Peak Power Warranties” do not cover any transportation charge, customs clearance or any other costs for return of the MODULES, or for reshipment of any repaired or replaced MODULES, or costs associated with installation, removal or reinstallation of the PV-modules”

If you have any concerns about the warranty from a pv manufacturer you can download a copy of the warranty from their web page download section.

This way you can read it for yourself rather than take the company at their word.