In the past my durability issues were guides that bent easily, rings that fell out of guides, and handle parts that came loose. Performance issues were rods that weren't centered on the spine, blanks that didn't go all the way through the handles, and overall really "soft" sensitivity. For reels, it was bad drags and kind of freezing up under load, not to mention poorly designed bails, spools, and line leveling. I haven't bought a cheap setup in two decades so just assumed they stayed bad.
These rods and reels have been tough. Those kids are hard on stuff, and no failures yet.
None of the issues you mention above. Not soft, they have a sensitive, blank through to the butt, with very smooth reels with good drags. Infinite anti-reverse with no slop. Have caught numerous "over slot" redfish like in the pic above, and they are strong and pull a lot of drag on 12# braid, but no problems.
The one exception to your list is that I've never checked the spine on them. With a spinning rod, finding the spine really doesn't matter, although I always do when I build mine, out of habit. These rods are good performers in my opinion, and I'm pretty picky about my tackle and I have fished more than most, even having hook and line commercial fished for a couple of years.
After using these combos, several guests went out to buy one for themselves. Turns out, the normal price for that combo was something like $79.99, so they weren't super-cheap, just heavily discounted.
Even at full price, it's a $40 rod and $40 reel. I would happily pay $39.99 for either, and not look back. I'm pretty impressed with the Lew's brand. I like the reels more than many of my Pflueger and Daiwa reels, and I've never seen any $39 rod that are their equal. Not many $79 rods are their equal, but It's been a while since I bought a store-bought inshore rod, so maybe quality has gone up across the board.
A good commercial-built rod that I used to like were the Bass Pro Extremes in the Rich Chunn 6'6" MH. Those were really good rods for $99, and even when they went up in price, they were worth it.
My fav are still Loomis, but they are very expensive. The Mag Bass GLX is still $550, even from Walmart and they are more in some places. Look here:
https://www.walmart.com/ip/G-Loomis-GLX-903C-MBR-Casting-Rod/5499506044
I started building my own rods for 2 reasons. Cost, and I couldn't find a spinning rod with the taper and backbone I wanted. Most "spinning" rods were flimsy. The Mag Bass series are excellent.
Before Loomis stopped selling blanks, I could buy a MB804, MB805 or a MB844 blank for about $69, so I could build a high-quality rod for about $100. When D&B rods went out of business, I bought 6 of those blanks on clearance for something like $39. I only have ONE left, and I'm holding on to it! Awesome rods for what I do.