I picked up a new Series 2 Harbor Freight 56" box over the summer that was a floor model, marked 25% off. I had some major projects to tackle this summer, so I couldn't go for the full stack all at once. After I earned a little extra money, I purchased the matching top. For the price, I have no complaints. My only observation is that there is a slight color variation between the top and bottom box; the bottom is a hair darker and glossier, the top is brighter but slightly satin. With grease on everything, you'd be hard-pressed to tell. I'm not terribly fussy, all my cars are imperfect too.
As someone who absolutely loves his US made tools, I spent years looking for a good deal on a larger US made box setup on the used market. I just couldn't locate anything with this amount of volume and durability for under $1k. So I caved and bought something Chinese.
For someone like me, an amateur mechanic who works on his own cars, this was a great addition to my shop. This year, I did two engine swaps in my driveway, working out of four smaller boxes with friction slides. I consolidated nearly all of it into the 56 top and bottom, and I retained my smaller 26" Series 2 HF roller as a mobile station to hold diagnostic, specialty, and electronic tools. An absolute game changer for me in terms of organization and productivity. I'm really happy, the only downside is now some of my friends think I am a "pro" mechanic and want me to help them fix their cars. "Yeah, no."