I've read a number of recommendations in cookbooks over the years for Koon Chun's Thin Soy Sauce. I picked some up the other day to use in some comparison cooking and eating. Off hand, it's been recommended in books by Barbara Tropp, Eileen Yin Fei Lo and Bruce Cost. On line, I mostly see recommendation for Pearl River Bridge and Kim-Lan.
Now, there have been plenty of taste tests of various soy sauces over the years by many people and groups. So here's some extra reading on that if you're interested.
http://www.flavorandfortune.com/dataaccess/article.php?ID=306 is interesting reading, but I wish they'd given more information from the testing. But it backs up what the owner said to me while buying the Koon Chun sauce. Everyone's taste is different. She prefers Kikkoman as it's not so salty.
In 2007 Cook's Illustrated did a soy sauce tasting and gave Lee Kum Kee's table soy their top rating for cooking http://www.cooksillustrated.com/tastetests/overview.asp?docid=10119. They don't let you link to the winners, but I think it was the Oshawa that won for table and dipping use. In their 2000 tasting, Eden won
But based on some of the Chinese recipes they've printed, I'm not sure Cook's Illustrated is an opinion I trust on this topic. Further, their list of soy sauce is full of Japanese style soy sauces with only two Chinese style, the Pearl River Bridge and the Lee Kum Kee. The La Choy is sort of an statistical outlier. There's certainly taste differences in the different styles used in different cuisines. And there are good arguments to be made for using a soy sauce of the right style for the dish you're cooking. For a foodie this might meant stocking a number of soy sauces. This doesn't work for my storage options and I mostly use soy sauce for Chinese style dishes. And that's where my taste preferences lie.
Wikipedia has a good starting discussion of regional differences in soy sauce.
My mother used La Choy soy sauce, probably because it was about all she could find on the grocery store shelves. I don't have particularly fond memories of it. Which leads me to my personal taste biases.
As mentioned, I grew up on La Choy. As my interest in food grew, I switched to Kikkoman in the later 80s, then used a fair bit of Wei Chuan, particularly their "pure" label. Switched to Low Sodium Kikkoman as my Meniere's kicked in. As I learned more about Asian cooking in the early 2000s I moved to Pearl River Bridge yellow label it's about half as much sodium as normal Kikkoman or Wei Chuan but with what I thought to be a better flavor for the Chinese food I cook. It's been my standard sauce for about 10 years and is my baseline for judging these sauces.
This tasting is not particularly wide ranging as it's based in what I have on hand at home. That happens to be Pearl River Bridge Superior Light Soy in the yellow label, Kikkoman reduced sodium soy sauce is here because I recently picked some up when cooking on short notice at a friend's house. And the newly purchased Koon Chun.
A Pearl River Bridge note. In the standard 16 oz glass bottle, the yellow label superior light soy is rated at 800 mg sodium/tablespoon. In the larger volume commercial containers, the same label is 1500 mg sodium/tablespoon. I don't know if its' just double strength or what the difference is.
This may sound horrifying but it wasn't bad really. Of course, i was working with samples of about 1/4 teaspoon each and took a few tiny drops of each to compare,then finished each spoon for a stronger comparison taste.
Kikkoman Low Sodium
Contains: water, wheat flour, soybeans, salt, lactic acid, sodium benzoate 575 mg sodium/tablespoon
Mellow, gentle meatyness, wheaty in the finish.
PRB Yellow Label
Contains: water, soybeans, wheat flour, salt, potassium sorbate 870 mg sodium/tablespoon
mellow, more complex flavor, not as much wheatyness , but it has a good balanced flavor.
Koon Chun Thin
Contains: Wather, soybeans, salt, wheat flour 1400 mg sodium/tablespoon
Stronger initial impact, salty, other complex flavors. Certainly the salt taste is very forward in this sauce to me as I don't eat or season at this level of salt. That aside, it has complexity I don't notice in the other two but could be an artifact of the sodium on me.
It's interesting to me as I typed in those ingredients after tasting them. Kikkoman has more wheat than soybeans, the Koon Chun more salt than wheat. And that's clearly reflected in their tastes.
Next up was used in a dipping sauce for pot stickers base in black vinegar, soy sauce and ginger with a little sugar I've developed this sauce with Pearl River Bridge over the years. I kept the ratios the same in each batch of the sauce. I tasted the sauce straight before using with the pot stickers.
Dipping Sauce straight
Kikkoman: Fruitiness of vinegar and ginger is pronounced
Pearl River Bridge Balanced complexity but it should be as I developed the ratios for this sauce with PRB.
KC saltier impact, stronger finish with greater complexity in the finish
Dipping sauce with the potstickers. The family participated in this part of the tasting and they were tasting blind.
Kikkoman. I thought it was just OK, a little insipid against the potsticker. My wife thought it just tasted weird. Kids thought it was off.
Pearl River Bridge is the baseline for this group. Everyone liked it better than the Kikkoman but were not as vocal or clear about it.
Koon Chun was given the better marks, Comments were more flavor, awesome tang, better. I think this was the most interesting sauce of the three though not the best taste which I'd give to the PRB sauce. But I wasn't tasting blind.
Which leads me to my caveat for the dipping sauce test. As a cook, I've learned to season to taste. I would not have left the Kikkoman nor the Koon chun dipping sauce at those levels of seasoning. As they taste different, they need a different ratio of the other flavors to come into the proper balance. The Kikkoman needs less vinegar and ginger and sugar to balance. The Koon chun needs more. And Kikkoman's at a further disadvantage as it's the wrong style of soy sauce for this dish. So looking back at the taste tests links in the beginning of this post, I question the validity of those taste tests particularly the Cook's Illustrated one. It's not fair to the ingredients to ignore their flavor qualities and not correct the seasoning. Whatever sauce was used to develop the recipe will usually be the one that tastes best.
So, what's my result? Koon Chun is a good tasting sauce with increased complexity. You'll need to adapt your dishes to account for the shift in flavor, particularly the higher sodium. If you already use a high sodium sauce, Koon Chun is definitely worth trying. For me, it's just too much additional sodium because of health limitations and Pearl River Bridge is a good tasting soy sauce for Chinese style dishes.
And like the flavor and fortune link or the advice of my local store owner, it's worth tasting different soy sauces and finding one you like.
I'll need to try some Kim-Lan when the Koon Chun bottle is almost empty to broaden this taste test.