I agree IanB, but for hand soldering stations the standard has plateaued. Its born out of the original MILSPEC MIL-STD-2000A, and the commercial version, IPC, incorporates I think, the military standards and aerospace standards. These include assembly techniques too, but we're only interested in stations standards, which has been stable for far over 10 years.
For each individual China branded stations, its hard to say its =,> or < than a true Hakko, since the actual performance of each clone, due to their quality control, can vary. With the real Hakko, you know its very likely to meet the specs they publish for the entire product line. So if you buy one on the praise of a post on eevblog, your unit will likely be more variable more than a brand with better assembly practices.
But, if the = > < capacity is fairly small, it may not matter at all. For example, if the green line is the clone station [ see post on this thread for details], it soldering capacity may not be a problem for an individual user, but it would fail IPC station standards. A user may only notice differences after having used an IPC qualified station then switched to a lesser station; moving 'up' from an unregulated iron, anything regulated will appear a big improvement.
There is a recent post on eevblog by Fabio with a heating curve of his Chinese station, it looks similar to the green line; see that thread for more details.
But the difference in cost is often the difference in making the unit fully meet IPA soldering station standards.
That isn't necessarily a good thing. History shows that standards emanating from industry associations never get simpler. They get more and more complex as everyone's vested interest gets thrown into the mix and added to an ever-increasing check list of items.
For a many purchasers the standard may contain items that increase the cost but have no relevance to the way the product will be used.