Roof A/C replacement options 2004 Minnie

[Marty57]

I've have a 2004 32' Class C Minnie; I think it's time to replace the roof a/c. The system is working but, when the coach is hot inside the unit just can't seem to get the air temps to drop very quickly at all. Being 17 years old, I suspect it's time to replace the unit. It's a ducted, RVP 8330 series, wall thermostat control unit. It looks like the Coleman Mach 15 may be good replacement. What experiences have any of you had with this type of replacement or suggestions for replacement units and vendors. I'm on the central coast of CA but would like easy warranty coverage around the U.S. should we have any issues while on the road. Thanks Marty57