I find http://impossibility.org to be a fair bit faster and with a bit more control over options. Suggestion: it'd be nice if one could toggle between what registrar they wish to use and have the URLs automatically updated.
I'll work on adding more registrars, this is planned.
The site is slower than normal right now due to increased load, but should return to normal after the HN spike. If not I'll more workers.
My goal is that you should never have to wait for results. By the time you click "Load more results", they should already be available.