Having sold both subscriptions and CDROM based B2B software, I can tell you with confidence that it was easier to sell a $2,000 software package once, then a $200 monthly subscription. That was my experience in the B2B world about 20 years ago.
But once you hit consumer signups or bigger prices it gets much harder.
They are very very reluctant to purchase subscriptions, even if it's year to year cancel any time.
Good work selling a subscription after already charging a one-off fee!