Application is 1971 Duster with Gen III Hemi, A/C. What re your experiences with these guys?

Painless is anything but, Francis is A bit better,
I would suggest an American Auto wire kit, For a totally custom or race car, hiway 15 kit will probably fit the bill depending on the number of accessories

I used both and both were not painless. The painless kit was just a bit more mopar specific.

The Ron Francis kit uses a proprietary black box that no one can fix but him. Painless is better, but neither are going to be simple to install. American Autowire is good and another good one is "Its a snap". Any one of them will work, its pretty much personal choice.

American Auto Wire

i've heard good things about ron francis. i have been looking at the xp 777. idk what kind of box it would have since older mopars don't have computers. they have a life time warranty for as long as the car is on the road. in my case i have 70 B body, that i plan to update with some bells and wistles. AAW does only has challenger/Cuda kits.

I cannot speak for other suppliers, but have Ron Francis system in 59 Vette Resto-Mod.

The color coding for their wiring circuitry is completely off from stock GM. Can drive you into a frenzy when troubleshooting electrical glitches.

I did my 69 roadrunner last winter with the Ron Francis kit,tech was awesome
,second to none,highly recommend