Just watching the match on City+. I'm too biased to have an objective view on the penalty decisions. The Sterling one was soft and shouldn't have been given but you're right it shouldn't have been overturned.
Gundogan was bounced off the ball by Iwobi, body to body. Probably wasn't a pen but I'd have wanted one. Bernardo was kicked on the bottom of his foot when it was in the air. Think Walker had one the same given against him last season. It was difficult for the on field ref to see but I'm pretty sure VAR was in operation yesterday