I used to love to watch Purvis Short shoot those ceiling-scraping rainbows. Best form? Ray Allen. Dude's form is picture perfect. Don Eddy would be proud.
I'd say for me that jordan had such grace and form on whatever shot he took especially his jumpers. Him being able to keep his form even in the toughest shots was what made his shot so great. As for mechanics. I'd have to say steve kerr. That guy looks like a robot on every shot. consistency and rhythm is his game.
I know I'm coming late, but I think Jayson Williams is the best pure shooter of all time. He was murder.
Yes, Purvis Short. I'd have completely forgotten about him by now if he didn't have such a beautiful jump shot. I don't think he had 3-point range, but anything closer, and it was money in the bank.