Hello everyone, regarding the PA 500 and PA 800 been able to overwrite the factory styles in case you run out of room (Most likely on the PA 500, since the PA800 also has the Favorite section same as the PA2X that is HUGE).
Yes, is possible, I have done it in BOTH, the 500 and 800, actually, also in the 2X too.
Is very powerful to be able to also RE-VOICE the Factory Preset styles too, also change the STS=OTS in Yamaha lingo....

I perform most of the time on the T4, but, I do not let go my PA500, if I need a style, I make it on the PA 500, then I convert it for the Yamaha and is done.

In many cases is actually faster to make Backups depending on the case of the performer, and load-Restore them and by the way, I recommend NOT to use the Compress function, this makes it to load or save much slower. As an example, I most of the time play at Senior Dances, and a fewer times I play at some private parties, this for Mexican people.

The advantage of the Backup vs the SET, is that the Backup not only contains all the set data, but, like in my case, I have replaced many Factory styles that I never use, like Rap, House, etc....besides my Performances/Registrations, user Voices, on the Factory presets I have change the STS, etc......so, this is much powerful way to use the most potential on the keyboard, and I simply re-load/Restore my backup for the Ballroom or for the Mexican parties....and is done in few minutes.

I did show how to use this feature to a Croatian guy that plays on weddings and use lots of User voices, samples, plus most user styles and performances, to simply use this feature and is very handy, he customized to have 2 or 3 different Backups per set, when he finish a music set, just begins the Restore backup for the second set, and after he takes a small break while is loading, his PA800 is ready to keep the party going.