I had an unfortunate experience after eating a big slice of my mom's chocolate peanut butter pie and went off the chocolate/peanut butter pairing for years. I can tolerate it now without gagging but still won't eat a peanut butter cup because a decade of living in the UK has made eating US chocolate a gagging experience...
I like Jif, my family send me big tubs every once in a while. The type of peanut butter available in the grocery stores in the UK aren't the same, definitely not creamy enough. I'm not allowed to eat it right now because the fat content and my gallbladder aren't getting along, but if I'm completely honest the perfect peanut butter sandwich is:
cheap, soft white bread
creamy peanut butter
I don't buy white bread though, so that is a real indulgence. I hate grape jelly, and I have always been creeped out by those jars that have the peanut butter and the jelly in stripes, you have to have them separate on the bread!
I will also quite happily eat what I call a "smooshed" peanut butter sandwich - you only put peanut butter on the bread, and then flatten it out completely. Peanut butter, honey and banana is pretty good, as long as you can keep your banana in check as it always wants to escape.
I did once know someone who eats (UK) peanut butter and cheese sandwiches. That idea has never seemed a particularly good one...