SaaS founders: did paid ads actually work for you?

I’m curious about real experiences not theory. If you’ve run ads for your SaaS, I’d love to hear:

• Which platforms worked best (Google, Meta, Reddit, etc.)
• Your budget when you started
• CAC vs LTV, if you’re open to sharing
• What kind of ads converted (pain-focused, demos, testimonials, etc.)
• Biggest mistake you made
• At what stage ads started making sense (pre revenue, early MRR, scaling)

Also, if ads didn’t work for you, what did instead?

Looking for honest insights from people who’ve actually spent money and tested this.