I can't say that it was what finally "cured" PF for me, but it helped. I wore it at night and while sitting around the house. My foot would fall asleep after a little bit, and I would take it off, but it did help stretch me out.

What also seemed to help was to keep a water bottle in the freezer and then to roll my foot over it a few times per day for 10 minutes. I also kept a tennis ball and golf ball in my office to do the same (massage basically).

I think the ice massage helped the most. I also did try to do some wall stretches with my calves, but I was not religious with those.

I also wore shoes inside (instead of going barefoot at home), and I used some of the Powerstep inserts as well.

I'm not sure if you are a runner, but my PF was from running. I was able to run through it by backing off a bit and sticking to flat surfaces.

Here is a good link with some other details.