If you think this looks familiar, it's probably because I wrote about 'Overseas Dragon' last year. 八方雲集 is a similar chain (akin to BK vs. McDonald's in the potsticker world). In any case, I did a pretty crappy job explaining Taiwanese potstickers last year, so I'll try to remedy that with this post.
Most people in NYC have had fried dumplings from Vanessa's, Prosperity, Northern Dumpling, or any of a number of the 5/$1 joints. They are, simply put, just wontons that get pan fried. Nothing more, nothing less. That isn't to say they aren't delicious, but that's not what I think of when I see the words '鍋貼' on a menu. Nope, the Taiwanese potsticker is an elongated wrapper that houses a thin strip of filling, most commonly pork with cabbage, but other varieties do exist (curry, kimchi, shrimp/pork, crab/pork are the others I've seen), that gets pinched in the middle, but not at the ends. They're basically like mini burritos that are open at the ends. Unlike traditional wontons which get boiled first, these go straight into a covered wok with a slight amount of water and a fair bit of oil, coming out with charring only on the flat bottom side. As a result, you end up with a string of potstickers that are conjoined in rows of fried dumpling perfection.
The 鍋貼 from '8 Upway' aren't tremendous (not unlike their brethren from across the hall), but you shouldn't expect them to be. It's basically fast food. At 4 NT per for the original pork filled ones, you can get 8/$1. At that rate of exchange, I would've been happy if they were even remotely close to what you find in NYC (and boy do they exceed that). In the end, you'd be pleasantly surprised by how good they manage to be. The skin is thick enough so that each bite is satisfying, but not so thick that it's a chore to eat. The filling is certainly tender and juicy enough, but small pieces of cartilege/tendon (or offal matter) are still present to remind you that it's a cheap street meal. Basically, don't expect the world, and enjoy the fact that you can buy 100 dumplings for $15.
I also ended up ordering a hot and sour soup because it was 25 NT. It just seemed like a good idea at the time. Asian people love drinking soup prior to eating their meal. I don't have that habit, but eh, it was pretty good. If I had to rate it, I'd say it's better than the average soup you'd get from your local delivery place, but nothing to go nuts over. In summary, fast food dumplings are good by me. As for 'Overseas Dragon' vs. '8 Upway?' I'm not entirely convinced they're not the same shop with different names (my suspicion stems from the fact that they seem to sometimes use the other store's plates).