I used it for quite some time, even bought a license but then dropped it when when they dragged their feet for years with utf8 filename support. I think they never fixed it.
I've using it since version 1.52 AFAIK and this is FIRST app i install on fresh Windows.
I also recommend Everything. It's the best file searching app I've found for Windows that fits my searching style, just type a regex and give me what I want.