Honestly I have used Bio-Spira (cheap stuff available anywhere) the last 3 or 4 times I started the quarantine up and added fish the next day and never had ammonia register on the warning badge. Bacteria is bacteria in my opinion. Maybe the more expensive ones have more live organisms? Some kind of additives to extend the life? But it’s not like they’re making their own brand of bacteria. The same stuff that’s been processing nitrogen since living things have been in water on the earth... it’ll get into your aquarium no matter what you do. Add it... feed it... don’t... it’ll get there.
Welcome to R2R!
Welcome! I used Seachem Stability with a pinch of fish flake food every day for 2 weeks to cycle. It worked great and was a lot less expensive than some of the other brands.