I've been to Great Adventure several times this summer and the Fastlane (a/k/a Qbot) is dreadfully unfair. Actually it is more than $20 i believe. Isn't it 20 for one person and then 10 bucks each additional person. One positive aspect is that the lines at GA are unreal, especially the new Superman ride. Although you really can't do much during your wait time, as all the rides have enormous lines equal to your next ride time, you can at least avoid being out in the heat and the sun.
As for Universal, it was my understanding that they recently started charging for their version of fastpass. I read that on this site recently regarding someone visiting Shrek 4-D. I haven't been to universal since summer of 2001, but I do remember that their version was a bit difficult and you waited way too long on their fastpass return lane.
Frankly, just being impartial WDW's version of Fastpass is still the most superior and the fairest. It's open to everyone at no extra charge. Your return wait time is very minimal. There are always several fastpass booths. I have recommended Fastpass to my friends who are first time visitors and they always return so happy and thanking me. I had a friend who returned just last week, first visit, and first for his son and family. The whole system made his trip far more enjoyable and relaxing.
Universal and Six Flags can't say the same.