I prefer Eagle One 20/20 to Stoner's Invisible Glass too.
Invisible Glass is an excellent product, and is clearly better than Windex or most other glass cleaners. However, I have noticed that while Invisible Glass does not streak, it does leave a fine haze behind that cannot really be buffed off. This is true no matter what type of buffing cloth is used (various MF towels, cotton t-shirt, newspaper). I have used Stoner's IG on all differnet kinds of windows and have always seen the haze. It's a minor thing- it can only be seen in direct sunlight at dawn or dusk- but it drives me nuts.
20/20 does not have this problem. If you buff it off well, it will not leave a haze behind. The trick is to buff it off properly. 20/20 will not haze, but it will streak if it is not buffed off right.
I fold my MF towels into quarters, plush side IN. I spray the 20/20 on the glass (3-4 sprays for the whole front windshield is plenty), buff with one side of the MF towel, than flip the towel over to the opposite side, which is dry, and buff again. This gives perfectly clean windows with no streaks.
Again, Stoner's IG is a great product, but I do prefer 20/20 for these reasons.