As the Reviewer and builder of the Yamato in that review all I can say is you get what you pay for. The kit is VERY expensive, even at the steep discounts some places have it at, but a pleasure to build and I was still happy to come into the hobby room every morning for the 7 weeks or so it took to build it.
Now, the older Yamato kits from Tamiya can be brought up to about the same level of detail but it will take a full suite of photoetch and brass and various other detail parts. You are putting a lot of extra time and money into an older kit with good but not stunning detail. It can be done, and you can space out the purchase of the various upgrades needed so you don't get hit with the whole price all at once. But the final cost is going to come out very close on either kit.
It's a choice every modeler has to make: your wallet or your time? Which is worth more? The new Yamato needs the degaussing cables, the metal gun barrels, and a railing set but that's all. The kit is stunning and fits beautifully. And the final product is a real show stopper.
The older kit will take a healthy amount of upgrades and a lot of modifications to approach the detail level of the new release. The time invested will be quite large. As will be the money. And in the end the new release will have sharper detail because that's how it was molded in the first place.
There are a lot of subtle differences between the new and old kits with the new kit being more accurate, but a lot of people really don't care if the bridge is perfect or if the 03 deck shape is off slightly. And honestly no one would see the differences unless they were a real Yamato fan.
Either ship can be built into a stunning and award winning model if the builder is good enough to pull it off.
With all that in mind, you can make your choice.