Non recurring credit based pricing vs subscriptions or lifetime pricing

Just for the context of the SaaS in question: Working on a product that lets you perform two types of actions: scan a site's GTM setup and search list of sites using a specific marketing technology.

Now the more I talk with my users, the more I get the following feedback in terms of pricing:

1/ Subscription is the default expected pricing. 2/ Credit based (like buy 10 scans, use it whenever you want) is what would my users prefer.

And as I look at other companies, it's does not seem so common to have a non-subscription backed credit system. Zapier or Snowflake for instance, lets you buy amounts of credits but you're still required to subscribe monthly.

I am raising this discussion because I also see a rising trend of SaaS makers selling their product for a flat, one time "lifetime" offer. And I think that this credit based, non recurring system, could be a better middleground pricing option for both the owner and the customers.

One caveat though, is that if you use Stripe, you need to implement the logic yourself as this is not yet supported natively by Stripe.

WDYT?