Personally, I think Porsche make better track cars. But the GT3RS and 360CS compared, is like comparing slow cooked roast beef with beef sirlion; its just based on what you like. It has been said that the Stradale is easier to manuver simply because it isn't manual, but F1. It has also been said that the GT3RS is more pleasureable, less hard to cope with and meaner looking. Well the only way we can really distinguish which one is better, is by pointing out the negatives each car may have. I've driven a Stradale, but not a GT3RS, of course they wont be coming to the states. One bad thing about the Stradale is, on long drives (over 40mins of driving) the sound gets too exessive, too loud in the interior. Its a lovely sound for a quick joyride but for a drive all the way tot he track you will be tracking it on, its probably not as pleasent as the GT3RS. On the track, the Stradale has grip, it reminds me of an Lotus Elise, so light and just the right amount of power. The Strdale has very few flaws once you get on the track- it never slows down or loses any kind of torque and it is quite simple to operate. Basically, the Stradale does better WITH the F1 paddles than if it were given a manual. The CS has so much jumpyness that at the apex of a turn, you could end up sideways if you punch the gas too roughly. Everything is a process with the CS, and that is the difference with it and the GT3RS. The GT3RS, like any 996, works well with the 6spd manualbox. With the GT3RS you can probably punch the gas at any moment and be able to powerslide much easier than the 360CS. Flaws of the GT3RS in my opinion would be: flamboyance and the look of it. It just doesn't look as pretty as a Stradale, hence it looks meaner, more aggressive. And the coloured rims dont really help it, but those cosmetics dont matter.
The GT3RS has the least flaws and therefore in my opinion would be the best bet between the two. The thing is, neither car really have major flaws on the track, they both get a similar lap time, it shows.
The Ferrari is more loveable, the Porsche is more usable.