All non inverter. Currently using few Old York 1hp and 1.5hp, Panasonic1hp, Mitsubishi 1hp. Old York is very reliable. Bought second hand more than 10years ago still going strong. Compressor is a little louder than the others. Panasonic has no issue whatsoever. Mitsubishi is also running well. Compressor is quieter than the others. All AC are more than 10 years.