I was under the impression that shoves at the net front or the slot (close to the net) were free from penalty calls, but I don't think I've ever been able to successfully shove someone there without it being called interference. I'll try to grab a clip next time.
Please do. I use push checks pretty frequently and haven't been called. I did have someone recently send a video showing they took an interference call in this situation about 10% of the time they use push checks. I also hold in LT, but not sure if that helps or not. I'm looking in to that.