That is certainly a better value option if you can still get the drivers and amps for a reasonable price over there.
I went the DIY route as well and build 2 of the VBSS style subs. I wanted to build something bigger, but my wife vetoed that. AVS forum has plenty of information on design options you have.
You obviously didn’t read the article as creating more stable schedules is exactly what they’re doing.
Is it enough, probably not. But let’s not make up lies.