That's correct. Without a filter, I think the resulting photo is similar to regular 400-speed black and white films.

Somewhere on the spec sheet or product info page on Freestyle, it mentions that a Red 25 filter isn't adequate to result in the infrared effect. You also can't use the B+W infrared filter that blocks all visible light. It will simply result in a blank negative (I know this through experience).

I think the film is somewhere between Ilford SFX and Kodak HIE.

When processed, the film isn't nearly as curly as Kodak HIE.