Out of the haul of games I picked up I found only two that didn't run. It's hardly the biggest problem as I still have over 20 that play superbly and what games they are. Mouth watering.
I will keep the non-runners and take them back next time I go to the shop but that is likely to be towards the end of the year so I suspect I won't get much in way of refund. Maybe they will simply swap them for new titles?
I won't lose much sleep over this though and I am so chuffed with the games that do work. Simply stupendous.