Converse do stretch, yeh. They can hurt abit when you first wear them, but that does entirely depends on the person. Converse are one of the best shoes to mold around the foot, once they have they're stupidly comfy. Just don't wear them if its really hot and your feet easily swell, they can get slightly uncomfortable.
Watch the sizing though, they're big fitting. When people are buying Converse for the first time, I bring down the size they ask for as well as the size below. 9 times out of 10 the smaller size fits better.
You have to remember they are a tight shoe anyway, but like I said, they're great for molding to the foot.