I like that I can get triple-butted Pillar spokes in both 1.8 and 1.5mm center-section sizes (TB2015 and TB2018), but I had one break on me a few years ago on a brand new wheel, and have been avoiding them since. That incident might have been a fluke though, so I'm wondering what peoples' opinions are on these spokes? Has the quality changed or improved at all over the years? Searching around the web, I don't see too many horror stories (none at all really, except my own), but I also don't see people lavishing praise on them either. Maybe because they aren't all that readily available to end users except from BDop, or indirectly through buying prebuilt wheels.

Is there any particular reason to get them? Given the number of makers of well proven spokes (DT, Wheelsmith and Sapim) why use a questionable brand?

never heard of the brand, myself..

No urgent reason. I mostly use Sapim these days but will use DT or Wheelsmith without a second thought if it makes sense for the application, based on price, availability of a particular length or style, etc. Just wondering if Pillar can be added to that list. They aren't exceptionally cheaper either, at least not the silver ones.

My old Token wheels have Pillar spokes. I've had them for over ten years with no problems

I've built with Pillar spokes. Matter of fact, I'm in the middle of building 15 wheel sets for my largest client with straight gauge Pillar right now. Their choice of materials, not mine, but I have had no negative experiences. Unless you count the fact that their black spokes are powder coated and I have to clean the threading dies more frequently.
They are made by Sha Dar in Taiwan, and the Taiwanese have most of this stuff figured out.