I have tried all three of the knots listed above and I feel like I am quite a picky knot person. They are all good knots. Personally I use the Albright, but only for the simple reason that I can tie it easier and quicker.
FG sounds like a great knot, but it lacks the ease and consistency of the uni/uni.....I still use the FG, but only when I'm rigging at home with good light. Albright has slipped wayyy too much for me.