If you are swapping out stuff all the time because you like to tinker then get the best deal out there because you are going to swap it out anyways. If you are looking to upgrade and never mess with it again I would strongly think about warranty over saving a few bucks. Rain, riding, etc. is never fun to deal with when amp or radio fries. Some places honor warranty by the customer having to send in their busted product to the manufacture and having to wait for a replacement product, and that down time sucks. So consider warranty and technical support on setting things up in your spending math.