First off I should be very clear that this was in a shopping mall so I already wasn't expecting very much from it. All around the world I feel like the worst possible option you can head towards is to go to a sit down restaurant in a shopping mall because the space limitations and the regulations they have about what sort of machines you can use for cooking because of fire codes severely limits the quality of the food they can make for you.
There are a ton of Korean steakhouse restaurants in Da Nang and all over Vietnam, but this is the first one that I have been to that wasn't catering specifically to foreigners as most of the crowd was Vietnamese.

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So first off, what makes this place "Korean" in my mind might be a mischaracterization. I'm not really 100% sure about if I am putting that correctly. It's Korean in the sense that you cook the food at your own table and they supply you with the cuts of meat. There is also Kimji and i've never really seen that on offer if the place wasn't going for a Korean edge since that is exclusively a Korean idea.
So they have multiple types of buffet that you can go for at these restaurants and the raw food arrives at your table and you cook it at any pace you want to. Me any my friends were quite hungry to we cooked it lighting fast.

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And herein probably lies the biggest problem with this chain in a general sense. Because it is a buffet and there is nothing stopping you from ordering 20 plates of pork belly or whatever beef they have on offer, they don't really focus on having very good quality of any of these things.
If you go to a "real" Korean BBQ you order by the 100 grams of extremely high quality beef and pork and someone who works there cooks it for you while you eat. This is that person's only job and they are very good at what they do. At Go Gi House and I presume other places like it, if you want to undercook your meat and make yourself ill there is nothing stopping you from doing exactly that. As a precaution, we probably cooked our meat slices too long
The side dishes keep coming in Go Gi, but here is another limitation of a chain restaurant in a shopping mall: None of it was particularly good. Kimji I am aware has hundreds of varieties but this one that we had the cuts of cabbage (which is a major part of Kimji/Kimchi) were absolutely huge. They were like half-a-sandwich sized and this is no conducive to having a little bite to accentuate the flavor of whatever meat you just chomped down.
The price is fair enough I suppose and is done to, I presume, keep it in the affordable range for locals. It was 369K VND per person, which is about $14 a head. This is a good price for all you can eat beef and pork, but I think it should be pretty obvious that at that price point you are not going to be getting Wagyu and Kobe. Mostly our meats were tough and dry or they contained so much fat for flavor that they were kind of off putting and made me worry about what I was eating.

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To the uninitiated it might seem very odd that someone comes by with more flaming hot coals to put in the middle of your table and comes by I think it was half a dozen times to change out the charring tray while we were there, but this is just part of the process. I'm not sure why.
The staff were attentive and plentiful and other than the fact that the 1 beer we had each was served warm with a glass of ice, I can't really complain about the delivery of anything. They did a good job with efficiency I guess.
At the end of it all though I really though that this experience was severely lacking compared to going to a real Korean BBQ restaurant and just paying for a-la carte prices for very good meat. Most of this meat was rather tasteless until you drowned it in sauce, garlic, and kimchi.
Was it worth the $14? Well, I guess so, but to me I would much rather pay the $20 or so that it costs to go to the real places and eat a limited, but much higher quality cut of meat that is cooked by someone else.
If you are in Vietnam you will almost certainly see Go Gi House or something similar to it in ever shopping center but my advice would be to find a place that is NOT a chain, is likely run by Koreans, and costs a bit more. It really does make a huge difference.
There are multiple GoGi House locations in Da Nang and you can get to one of them easily if you are here. Once again though, I encourage you to look up the slightly more expensive and authentic experience at a "real" Korean BBQ rather than go to this.