It's primarily the handpiece and hose that feel cheap compared to the Metcal. Also, the cord just directly attaches to the unit: no IEC connector. All of my other soldering stations have a replaceable cord. The buttons on the front panel feel cheap and plasticky when depressed (and the left most one clicks differently than the other two).
I'll admit all of this is a bit petty, so apologies for that. I think I just had higher expectations. If I can get a unit with a good hose, perhaps it will be OK.
The Metcal has an inner supporting spring coiled inside the hose, to prevent kinks and deformation. The hose wall is also much thicker. The handpiece doesn't feel plasticky (and the Metcal handpiece is considerably smaller) compared to the Quick.
After I discovered the sad shape of the hose, I searched and found the thread that you refer to (the other guy that had a unit with a bad hose). Mine hose certainly looks worse than his, I suspect that no length of time will ever fix the kinking in spots, as they compound-bend-twist-folded the hose to high hell.
I can't speak to the inner build quality of the Quick, I assume it looks similar to the pictures you posted. The Metcal is better built inside compared to those pictures, but it's also extremely simple. The Metcal has a cast aluminum enclosure, the (one-sided) PCB is nicely done, wiring is impeccable, the pump is very high quality etc. It's also super simple which is my primary complaint: has no screen or visual temperature feedback, the air control is literally a physical valve, and the simple circuitry uses that stupid 90 second timer.
I was positively surprised in the handpiece stand for the Quick: from the pictures, I thought it would be plastic but it is cast metal. It does have a cheap feel to it, but oh well, I like how the stand is separate.