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I just bought a Phantom Grip 905-Gold for the rear diff in my 99 Legacy L yesterday.
I installed it last night and drove it for about 50 miles today.
When installing it, I had to take all the spider gears out and grind them flat so the unit would actually fit in between the gears, it was actually hitting all the gears. It was not as straight forward as I expected, but not excedingly difficult; although I am an entry level mechanic, and have a $400,000 garage to work in.
I honestly was expecting more, but it has only been 1 day, and apparently it takes 300-500 miles to completely break in and work at it's full capability.
This is what it does so far:
In the snow and gravel, the car has massive oversteer, sometimes, but not much different on the street. The center diff in my car has 100,000+ miles on it, so i'm not sure if all the power is actually making it to the rear; and the reason I say that is that it seems to spin the front tires much more than the rear.
Also, when the car is in the air; if you spin one rear tire, the other one really doesn't do much. At first, it spins like an open diff, but as the tire slows down, they will spin the same direction. And when you spin the front tire, both rear tires will spin the same direction, until one the touched, and then it stops, but the other will spin.
I understand the mechanics of it, but can't grasp how when spinning one of the rear tires, the other just basically sits there and does nothing. And open diff would spin in reverse, due to the spider gears; and a LSD will spin the same until forced to do otherwise.
I just don't understand how the rotating force in the phantom Grip is exactly the same as the turning force in the spider gears?

So, has anyone ever installed one of these in a subie before, and how well did it work?