Is Reddit good for marketing a SaaS app?

By my experience, reddit is good but need to follow the rules for the subreddit.

Depends how you are going to approach it. If you go for paid ads - you need to benchmark it against let's say Google Ads and see what performs better for your audience. If you want to use communities to promote, as already mentioned here - be aware of community rules and do not spam.

Only if you're doing content marketing that is not an overt pump of your product -- they tend to rip those to shreds publicly. I'd also be careful have metrics on users who do subscribe, as there are many on Reddit who will demand refunds 10s after signing up because they really couldn't afford it in the first place but curiosity got the better of them. It can make churn rates look poor so be sure you have origins assigned to them so you can make sense of churn numbers later.

Reddit is one of the most dangerous means of communication for marketers. The community can be really harsh on commercial messages.

I help a lot of people market their SaaS on Reddit. Here is an example: https://syften.com/blog/post/one...