> because I'd hit some limit (..) 10 days max is pretty bad

The free(!) plan includes 300,000 queries per month. That is transparent everywhere. On the website, pricing page and in the dashboard. You can even see how much you have already used. That's pretty fair for a free service for which you pay nothing. For me, that's enough for a whole month.

> (..) which doesn't arbitrarily stop working

1. NextDNS sends an email before the limit is reached

2. Once the limit is reached, no more ads are blocked, but dns continues to work