Good old classic,
Even for 16 years that's amazing quality, on of most fun mods for one of best years for IndyCar, just on the eve before split.
Car models are great and while I feel Menards would need small engine tweak for being more competent it's still great pleasure to drive with such cars.
It's also worth pointing that this mod got some good skin packs for few other seasons which even more enhances expierence. It's definitely one of rFactor classics.
iDT made one of best mods for rfactor and it's hard to choose one best, but I think this IndyCar is probably best considering all content they put there.