Forget letting the audience hear your best sound if you like. But do consider that if you have two powered speakers in place you always have a backup in case one fails.
I've had this happen only twice in the years I've used them but I was REALLY happy to have two when it did happen. It occurred once with the Bose Compacts and once with the Maui 5s.
With the Bose, the unit had to be replaced. With the Maui it was a simple loose connection where the power cord plugs in.
Being able to finish the job can mean the difference between getting paid and getting embarrassed. I prefer getting paid.