1964 Valiant "Get Runnin & Drivin"

I have a 71 duster I picked up couple years ago with original paint. The hood, roof ,and trunk lid needed to go to bare metal. No problem. I rest of the car , the original primer and the paint, that stuff is tough, and on there !!!! I applied epoxy primer and did the door dings, and I have no problem with that original primer/paint being left, but this car is the exception by far.
You have plenty to do before you buy paints. Like mentioned here by lots of guys, SP has good stuff. I don't think they sell topcoats just primer. I have used all products from TCP Global with good results as with Omi ( PPG second line) topcoats.
I also agree with driving the dart to the local PPG and have them scan it and give you a price just to know and be able to color match.
I admit I have never tried Summit paint products, they get it furnished from someone, be interesting to know who.
I always try to compare quality and price to everything as I can not just afford to go buy the best of whatever!!!