I went to Exotics Racing in Las Vegas this week to see if I want to trade my R8 V10 6MT Spyder for something else. I reserved a 570S, AMG GTR, and 458. When I arrived, they told me the AMG and 458 were both in the shop. I ended up driving the NSX and 488 instead.
NSX: Great overall car and much better than I expected. Fairly heavy steering. Great engine sound INSIDE the car. Very stable in corners and easy to drive hard. I think this is a strong competitor to the R8 as an every day super car. With used models in the $120k range and the ability to tune them now (running 10.6 at 130mph), it's also a good value. A couple of the instructors said it's the car they would chose to own.
570S: Lighter steering and lighter overall feel than the NSX and more fun to drive on track. Felt a little faster on the straight, but not dramatic. Foot well is a little narrow, but not bad. Nothing really to complain about as far as the driving experience. They have 3 570S and 1 720S at Exotics Racing. Only one 570S was running...
488GTB: Very similar to the 570S but about 10-20% better. Lighter and quicker steering, slightly better acceleration. I don't see it being worth the $80-100k premium over a similar 570S, but it's a great car.
I'm still very happy with my R8. It's just about perfect for a street car. The only one of these 3 cars that I would consider is the 570S because it's different enough in looks and feel plus it's insanely fast with a tune. Still trying to decide if it's worth the extra cost (price + warranty + maintenance). I might get one of the prices come down a little more, or I might just hold onto the R8 until the Tesla Roadster comes out in a couple years.