18 months ago EVERYONE used tar.
Six months ago, you would have got laughed at on here for using it.
Now it's ok again, so sayeth me. TF sucks sometimes :-
Anyway, I don't really see the problem with tar. To have decent brakes that hold, you have two options:
1) Set your brake up perfectly, nice bleed, find some good pads, get a nice booster, grind your rim every couple of weeks.
2) Use tar.