I use an OTC Genysis at the house.
We have probably at least 10 different ones at the shop. There is not one that does a "perfect" job at everything, but there are some that are much better than others. What sort of application are you looking to use it for?
The best one for your VW would be the VAGCOM being the factory tool. It is laptop based, you need to buy the OBDII cable that plugs into the USB port on your laptop.
On your Asian and American cars I would use the Genysis, or our Snap-on Verdict, neither of which are in-expensive for day to day personal use.