I think he's saying that the "17" series (117 and 217) are the last good Pioneer DVD burners.
We ordered a half-dozen 118s and while their burn quality and reading is fine, they have a terrible mechanism that can mis-grab a disk and spin it at high speeds, shattering it inside the unit. Not just crack. But explode it. Like, into a hundred shards!
If it was just one unit, well... but we've had 3 of those half-dozen do this. This is beyond 'coincidence' then and looks like a very serious design issue. The remaining drives are still functional, but those users are warned to always be very VERY careful in loading disks to play or burn. VERY precise loading is required.
I had hopes that the 20 & 21 series would be superior, but we've moved into Pioneer BluRay burners instead with a return to the good Pioneer standards.