Like Mitch I have pint batches of home brewed iron saturated aquafortis and try them plus Kibler’s ferric nitrate and various other concoctions on a test piece. It’s less work and less expensive reaching for an already made mix than ordering some ferric nitrate. But I agree that for anyone without access to a wet lab with 25 years of chemicals in it, making iron-saturated aquafortis is only efficacious as a fun project.
WOW! Mitch, K.J.K. is in 7th Heaven with that gun! That is a beautiful piece of work.