I've always run NR2003 at 35% race distance with everything set to 3x frequency. Exactly like everyone else says it just means fuel economy, pit stops and consistency are bigger factors. I've done the odd 100% race over the years and they're always good fun, but thirded is where it's at for me.
Actually did a full season with 100% races last year. It was pretty boring tbh lol, get the occasional wreck, spin once or twice, smash the wall down.. etc etc. No idea how many times I melted my tires off trying to play catch-up haha.
For example, Savannah, last Wednesday, was scheduled for 120 laps, or 60%.
This week's race at Charlotte will be 80 laps, or 20%.
Riverside will be 29 laps, or 15%.
All of those races will take about 1 hour.
I've run 500 miles (100%) at Daytona -
- and it was a hoot. Lost connection about 20 laps in, reconnected and was 2 laps down. Spent the next 160 laps working my way back to the lead lap (no lucky dog, race back, single file restarts). Missed a lot of wrecks (I'm in the black and gold Olds 'camera car').
Got back on the lead lap with about 20 to go and finished 4th.
Great fun. Biggest issue was getting to the bathroom and off pit road during a yellow without losing a lap.
One of the best parts about longer races is having a chance to make up laps and spots should something like a disco happen. If it's open setup, you have plenty of time to adjust. If it's fixed and you and the setup don't get along, it makes for the long day/night, being lapped over and over and over and over again, and that's not as fun.
No matter the length of the race, most important thing in my mind is having fun, giving room, being patient and waiting until "go time" to drop the hammer.