I am trying to get some info on a Payne Heating and Cooling system. Our Home is about 1800 sq. ft. and what we have is a PH13 split system heat pump with R-410A. The fan coil unit is a PF4M. Is this a pretty good unit and how does it compare to a Trane unit of the same size?

Payne is a builders quality unit made by Bryant. Bryant/Carrier/Payne/Day and Night units are all owned by the same gigantic corporation. You have to compare apples to apples when looking at equipment and then there is the price points to consider.
Payne is a good unit and will work as well as any other brand but the most important feature is th install. If installed well the unit will last a long time but if someone installed it that has no idea what they are doing then a disaster is right around the corner in the future.