Fwiw, I initially burned through the free searches in a few days, so definitely not enough IMO. Add the fact that free searches never got refreshed for my account, and I was pretty much unable to properly test the service for months. But bangs still work after the limit, thus I kept it as default given that I heavily use bangs to search other services.
Still I ended up subscribing, and after properly testing, I can recommend. The service is good, the blacklist feature is essential to me now; is just that the free tier is shit.