Im currently using a stock one. however after looking at the 800 dollar kit for the rack and pinion one, I believe I can duplicate it fairly easily using a small steering rack, and a carrier.
Once I have a steering rack out of a car I can use, Ill try to mock something up to test it.
Its just matter of finding a small enough rack in width. I'd personally like to go with a power assist rack to deal with my tire width at slower speeds.
It would use the stock VW steering components minus the stock steering box itself. It would work in the same way and should not throw off the steering geometry at all.