I am also someone that has never used a diesel additive. My dodge ram has 374,000 miles on it with no engine issues ever. Transmission yes, but not diesel.
/ Which diesel fuel should I use or does it really matter?
I'm heartened to hear that knowledge/facts are now more widely recognized. There are still the old superstitions, but they're dying out...
If your jurisdiction charges sales tax then off-road will be taxed accordingly. For me off-road even with delivery charges and taxes comes out cheaper.
I've only got a combined 1,600hrs or so with my tractors (lesser hours on my UTV and generator), but so far NOT using additives (other than stuff to keep fuel from gelling) hasn't seemed to be a problem: about 1,050 hrs on the B7800 and 550 hrs on the NX5510. Manufacturers generally don't state a need for additives.
Dye discussions pertain to the US only! Other countries use different dye colors/schemes.
/ Which diesel fuel should I use or does it really matter?