Not trying to start an argument, but the reason that stability claims to work is by adding live bacteria to your tank. Bacteria that have been stored at room temp for godz know how long. I seriously, do not believe that it will cycle your tank in a week, the bacteria required for proper cycling require 6 to 8 weeks to mature to the ones that eat nitrite and produce nitrate. No magic chemical is going to do it for you.
Even if you have zero ammo and zero nitrite does not mean your tank is cycled and you still need to add fish slowly. With no source of ammo (fish or decaying food or other matter) there is no food for both types of bacteria required for a stable environment. Fish will still need to be added slowly, and you can still have an ammo spike.
When I transferred my last fish to his new tank I took all the substrate, I was switching to a new type of filter so could not use the media but i squeezed all that "gunk" out into the new tank. I let it run for three days just to let the dark cloud settle and put him in. He is a 7 in Senegal, not a clean fish, and I did a 10% daily water change for three weeks, never had an ammo or nitrite spike.
A coworker of mine used stability and cycle and stocked her tank like the bottle said and kind of also with my advice. She had a 29 gal and added 6 zebra danios after a week of running with both chemicals. She, thankfully, listened and didnt feed them within the first three days and she still had an ammo spike. Should you choose to rely on chemicals instead of biology, watch carefully and be prepared to do water changes.
What works for some doesnt work for all.