It’s hard to describe them since Wei Chuan makes several different lines of dumplings as you can see from the web page, as well as tons of other stuff.
The ones I like best are the “High-End Dumpling Series” shown on the website. There’s also the “Shandong series” but I didn’t find them to be any closer to real Shandong dumplings in terms of flavor. The shape/skin is closer to handmade than the High-End series, but the flavor is not as good (I think it was too greasy).
Most of the other brands that I’ve tried from the Chinese grocery stores were not as good – some have bad wrappers, some have bad fillings, some even had tough tendons in the meat filling, a big no-no.
As for frozen potstickers, I have not tried any Chinese brands since I prefer them to be “open-ended” and fresh from the wok. But I have tried the Japanese style Gyoza from Ajinomoto and it was pretty good. I’ve also enjoyed some of the Korean potstickers, mainly the kimchi flavor.