Ask HN: How do you feel about UX/UI design subscriptions?

I've been working with software developers for 20+ years, providing UX/UI design services. I did that as freelancer, then an office job designer in companies of various sizes.

I'm now experimenting with marketing myself as a one-man studio for startups and small businesses [0].

One question that I cannot figure out my opinion about is pricing. I've worked with 2 approaches:

- fixed price. I estimate the cost of every project; I send out invoice at the end of the project (or as negotiated).

- hourly rate. I agree with the rate with a client; I work on tasks as they come along; I send out invoice every month.

Recently, I've been seeing designers (and teams) offering a "monthly subscription": Off Menu, Endless, Draftss, Rithmm, etc. The terms are more or less similar: you can make unlimited design requests, completed one at a time, for ~$5000/month.

I can easily see the incentive for the designer – but what about the client? Would you, as a client, use such service? Why or why not? Did any of you actually use it? What was your experience? I will appreciate your opinion.

Thanks!

[0] https://uxdesign.vlad.studio/