Great info macsnax. Your actual tested use, obsevations and results are much appreciated.
Though both are Bacillus amyoliquefaciens. SA's is strain D747 and hydroguard is proprietary and not listed.
Yup spyralout, I think you are right that HG has no smell because it is such a low concentration.
Every Bacillus I know of in a liquid application or as a contaminant in another cultured medium smells pretty strong when it is in a high concentration. Not that ya wanna sniff it, but its obvious hehe.
Serenade... yuck! Subtillis often like rotten apples or burnt bacon ( It is used in some fermentation processes)
The dry spores in dry applications not so much until it germs and grows and that depends on the medium.
The SA, is relatively safe , however some can/will experience an allergic reaction to exposure. So just use carfeully when spraying.
Z7 sds:
https://flyingskull.net/Dnld/z7-SDS.pdf