Their small dishes are better than the entrees. My best experience was when I went with a large group of people and shared multiple appetizers. Otherwise, I find the main dishes to be generally disappointing. They are not all that different from what you might find at other Asian restaurants (more generic Chinese than Malaysian).
Since 2008 or so, they also began to offer "Hong Kong style dim sum." Although the selection is limited and the dishes taste like reheated frozen stuff, I welcomed the addition. A Sunday brunch at Sun Penang offers at least a pale imitation of the dim sum experience (they'll even wheel out one lonely steam cart), which is the best we can get in Pittsburgh for now.
Of the dim sum items, I like: the stuffed eggplant. I also find that the Malaysian sponge cake, the baos, and the shrimp dumplings are pretty robust to reheating. If you are ordering to-go, you can revive the egg custard in your toaster oven. I am disappointed by: the turnip cakes (I prefer Rose Tea's) and the congee (Ka Mei's is marginally better).
Overall, their food is above the minimum threshold, but it's hard to get too excited about them.