PA systems. Advise please

[Mearas]

Please can anyone advise of a good mini PA system or personal PA system?

I need to buy one for a classical dressage clinic I am organising in a large indoor school.

Is there any calculation you can do that shows you the size of PA system for area of indoor school?

 

[Mearas]

Just bumping this up in the hope that someone has bought a system they are pleased with.