Since you say that you can get by without a bagger, I'm going to suggest that you give some consideration to the Husqvarna R 322T AWD mower.
It's articulated which gives you a lot of advantages of a ZTR and will handle hills like a billy goat.
HUSQVARNA R 322T AWD - Riders
It's articulated which gives you a lot of advantages of a ZTR and will handle hills like a billy goat.
HUSQVARNA R 322T AWD - Riders