OK, let’s compare it to what I do know:
http://www.la-z-boy.com/p/sofas/verve-premier-sofa/_/R-610667
It’s all priced a little higher than the sets that LaZyBoy is featuring. The LaZyBoy quality is higher, though. You’ll never take one apart and find webbing in the back supporting the cushions. It has serpentine springs in both the seat and back. Since seriously high quality webbing costs around the same as serpentine springs, why not use them in the first place? The answer is that the webbing isn’t real high quality.

You’ll find similar construction materials used in these MUCH cheaper ones:
https://www.ashleyfurniturehomestore.com/c/furniture/living-room/sofas/?icid=Living-Room-2B

Now, what matters most about those springs isn’t the spring. They’re all good quality, they all come from China and they’re pretty much all the same thing. What matters is what they’re attached to and how it’s done. Hardwood construction is good. Metal is better. Anything with engineered wood is bad. Engineered wood is most commonly this: https://en.wikipedia.org/wiki/Oriented_strand_board
There’s a name for laminated hardwoods. It’s called plywood. If it’s plywood, they should say it.
That’s because springs don’t break, but they can detach. They rip out a chunk of whatever they’re hooked to and curl up and die. This can lead to frame failure. Also, there’s no reason to use “hardwoods” and then support it with this trash, except to save money.

The next step up is this:
http://www.ethanallen.com/en_US/shop-furniture-living-room-sofas-loveseats?sz=36&start=36&site=
All of the frames are completely hardwood.

I wrote all this about frames because frames are a big deal on those mid century designs. Since they have a lean look, they don’t have as much of a frame as other styles. That means that what they do have has to be high quality and that tends to be a problem. Note: Every single one will claim to be high quality.

Now, something that’s important is the quality of the foam in the cushions. Good quality foam can last about forever. Low quality foam fails predictably in a year or two. More actual rubber in the product means a longer life as a comfortable product. You can only tell that by pinching it directly. Synthetics feel more crisp. That’s the best way I can put it. Rubber feels like rubber. They are all a combination of the two.

The cover or fabric should be mostly synthetic. It’s durable, breathable and easy to clean. If it’s woven and thin, it should have a thick, dense backing. Otherwise, it should be as thick or thicker than very heavy drapery material.

I hope this helps. Thanks for reading all this.