How does using this site compare to using regular font software?

It is a different world. Incomparable with any font software.

I think it's fascinating that one can use FontStruct's geometric shapes in practically limitless combinations to make alphabetic fonts or dingbats. And the creativity on display there is pretty impressive. You should give it a try. If you're not pleased with your designs, you don't have to make them public.

And that is exactly the difference with real font software where the designer him/herself determines the shape of each glyph, independent from predetermined pure geometrical shapes. Thus, incomparable.