I picked up a used 2016 GT350 last fall, but parked it for the winter before doing much driving. Snow isn't completely gone yet, and roads are still a mess, so it hasn't come out yet, and it is killing me.
I bought it from a friend (father of a kid I coached), so I had had it out a few times before I bought it. It was by chance I got it, because I happened to see him one day, and mentioned I was looking to buy a new one. One thing lead to another, and he offered his up for less than the average used one was going for.
Anyway, can't give you much detail about buying new. I haven't seen a R in real life yet, and only a few GT350's. Still haven't seen the new Camaro, but I rarely check my mirror, so that's usually where Chevy's are when I'm on the road
People will say the Chevy is faster, but as you mentioned, dealers are selling the Ford for above sicker, and the Chevy can be had for below. There is a reason for it. And if by chance GM gets a bit too loud and makes the mistake of thinking they are king of the muscle car, the GT500 will show up on scene and end that quick. GM should just leave trucks and muscle cars to Ford. Focus more on spending taxpayer money to sell average cars for below profit. Don't mess with the company that has the best truck, then went out and built the Raptor.
In the limited time I've been behind the wheel, I can tell you it's truly an awful car. It's a pain to drive, as it's way to firm and you kill yourself on every bump, sits so low you are worried about every curb / speed bump, and the transmission is useless at slow speeds. But the engine. Oh my the engine. Get a piece of open road and put your foot down. A few years back it was rated the 2nd best drivers car on the planet, only getting beat by the McLaren 570. I have to wonder what the McLaren does to be better than the GT350. Ford could easily add an extra $100,000 to the price tag, and it would still be a bargin.
So I wish you luck in buying your new car. If you want to save money, buy the Camaro and be despressed. If you want a truly great car, there is no doubt, get the Shelby