Often enough, some of us count Optiarc (which was partly, then wholly, controlled by Sony) as its own entity. For the most part, it used material from the original other half of the venture, NEC, for its own custom drives. Then Sony drives are counted somewhat separately, given its retail presence, while Optiarc was retail + OEM. And we would count the 7240S as an Optiarc, due to it being an evolution of older NEC technology.
Optiarc no longer exists. Once Optiarc ceased to exist, Sony also no longer rebadged drives from other brands (there most recent rebadge having been a LiteOn BDRE drive which also no longer exists, rebadged as both a Sony and an Optiarc). So there are no longer any new genuine Optiarc drives, nor are there any new Sony-branded drives to speak of.
As for burn results versus longevity for your particular media choice:
If the initial burn results are OK with this drive, then there is no reason the disc will degrade any more quickly than if you had used a known good drive. Just do like you would do if you weren't questioning the quality of the Asus/LG: keep an eye on all your archived media and reburn when necessary. Yes it is possible for a drive to do a bad job of burning a disc, but even that wouldn't necessarily accelerate the eventual failure of a disc unless the disc itself just went bad.
As for scanning reliability with your Optiarc:
In the past, NEC drives weren't counted as fully reliable, but by the time Optiarc came about, the drives seemed to have become more reliable for scanning (much more so than the average LG drive). It is especially true, however, that Optiarc drives will let you know when they don't like a disc, so if you're not having any issues reading back these discs in the Optiarc, and the LG (essentially) reads them, then I would trust the Optiarc to get a rough idea of how the disc looks.
Disc scanning in general:
Disc scanning can tell you only so much about the state of a disc. Primarily, it tells you if the disc could be read; if the drive struggled, it might indicate which area caused the struggle (or failure). It cannot directly tell you about all physical aspects of the media, but it can give you an indication if the disc is getting hard to read, and you can do a little inspection with your own eyes to see what could be causing the problem, or prompt you to do further tests with other drives.