Add heatstrip n hardstart to Duotherm BriskAir conditioner?

I can only help with Item 1. SPP6e is the one that one of our resident RV techs recommends, over the SPP6. It's interesting that SUPCO itself, recommends SPP6. They claim the PTCR in SPP6 gives a generator more time to ramp up to the A/C load, than the Electronic Potential Relay in SPP6e does. Still, I'd go with experience and install SPP6e. Our Coleman Mach has a hard start with a Potential Relay, and I carry an SPP6e as a spare. But I've never tried it.