Not many have the option to own either and fewer the option to own both. Some do, and their appreciation of these cars deserves special attention when they go as far as ordering two successive generations of the same hardcore model in the same color.
Both the 997 GT3 RS and the 991 GT3 RS are versatile enough to work well on the road, despite their unusually focused orientation. Through the experiences of a man who's more concerned with the performance of such cars on cross-continental journeys, we see how the exceptionally involving and unrestrained 997 may have the upper hand on backroad blitzes.
Part of that is due to the weight. The smaller 997 weighs in around 130 pounds less than the younger, PDK-equipped sibling. Less heft combined with a narrower track makes a massive difference when trying to place a car around rocks, cracks, and other imperfections flanking a public road. This certainty of the dimensions and a more involving-at-low-speeds nature—mostly due to more informative steering and an h-pattern gearbox—gives it a liveliness not necessarily replicated in its successor.
All that size-related friskiness isn't carried over into the 991, but that generation compensates with more tech and a versatility which few cage-clad cars can match. What limited the 997's front axle is compensated for with rear-wheel steering with the 991. More power, faster shifts, and more ability to focus on the driving with no concerns of a third pedal or a gearshift also make the newer car a better fit for the track—even if it has gained some weight.
Whether you're fond of the analog experience or something for which lap times take precedence, both deliver. After all, we're talking a subtle gradation of grey separating these two Viper Green vehicles.