I have been to Penn Mac a couple of times, and that has been over a period of a few years.
The first thing I found is that they seem to have a great selection of foods, but when I inquire about the price of various items, I find that I can get the exact same items at a better price at my local grocery store.
The second thing I found, on each of my visits, is that the staff are incredibly rude. Maybe it's arrogance, maybe it's unfriendliness, maybe a combination. But it's an extreme turnoff for me. I was completely ignored by more than one person when I wanted to ask about an item and I overheard cashiers and other employees being offensively rude to other customers.
I can say with confidence I will not return. Not only do I not need to hear the employees speak rudely to their customers, but I can get the same items at a better price with a 5 minute jaunt up the road with free parking. I would encourage more people who shop their to do some comparison shopping at their local grocery and support the place that treats their customers with respect.