Yes that's true, formalin is quite dangerous at 37%. That's why I made a diluted solution in a well-ventilated area (actually a fume hood) with proper gloves and proper precautions so it won't kill me even if I messed up badly. Then I can store the diluted bottle at darkroom and use it "normally" (not drink it nor bathe in it). Actually the "3-bath" (really 4-bath) amateur E6 kits like Tetenal have the dilute formalin in the stabilizer even today. It's not a safety hazard at low concentration with normal precaution. The bigger problem might be where to get it.

But, I'd guess that both Kodak and Fuji products are as good as you can mix by yourself, or better. I use Fuji without problems. I wonder why people are getting problems with other products. It cannot be that hard to make proper formulations.... But well, after seeing Tetenal selling only dead RA-4 blix time after time, I'm not so surprised anymore about these 3rd parties products ;-).