10-20 years ago, sure. Nowadays you can get basically the same product from LEGO compatible competitors for way cheaper. Dunno how many modern sets of the variety of competitor stuff you've assembled recently, there's huge variance. Some of it definitely has crap QC. Some of it is really, really good now. My wife put together some knockoff 8000+ piece set the other year and the pieces were basically flawless.
Where I've seen the difference is in the quality of the instructions (which matters) and the packaging (which arguably doesn't). The bricks themselves are, as you say, basically flawless.
