Which domain extension do you use for your product?

I was using .co, but changed to .net. There is also compatibility with the product name.

.io

While .com has proven to be preferred by search engines, I'd definitely encourage people to go for so non-common TLDs. I'm currently using ".ai" for www.oneaudio.ai however .io is alwasy great for technology applications. Another example is taking advantage of a TLD to extend words, e.g. "www.shipfa.st" by Mark Louvion.

.com - if you want to be seen, this is the way. I don't think Google favors other extensions, SEO-wise.

.co