The final verdict? They work, but not optimally, at least not with my welder. To compare with, the reference is Lincoln 5P+ 3/32" SMAW rods. Compared to the Lincolns, these India rods light up strong, have a forceful arc as expected, but the flux is what I believe does them in. They have a thicker layer of flux, which may "suffocate" the rod/puddle and can extinguish the arc if you don't hold a very tight arc. I never had such troubles with the 5P+.
5P+ is roughly 0.130" in overall diameter.
Blue Demon is roughly 0.150" in diameter.
For those not mathematically inclined perhaps thinking that 20-thousandths is nothing, that translates into 70% more
flux than the 5P+(!). With the Blue Demons, you literally have to have the flux scraping the joint at all times so the actual electrode is within the proper distance. Re-strikes proved more difficult because the excess flux really obscures the electrode from actually touching and initiating the arc. You have to scrap it or tap it somewhere to break off the excess flux to get a re-strike going.
That's my take on it at least.