Question about buying demo PA speakers

I'm thinking of buying a Mackie 12 Thump from GC because it was used as a demo which means it stayed turned on constantly every day for about two years. Does leaving a PA on all the time have any seriously detrimental effects on the internal components or otherwise decrease the life of the equipment? Sonically, it sounds fine. I would love to get this speaker since it's cheap, plus I already have one and a matching set would be nice but I'm hesitant to buy a potentially damaged speaker.