Depending on where your Dad lives as to where I would point you for more info but the Jura is certainly the auto of choice for both Cosmorex and Gilkatho (site sponsor links to the left).
I have had a few shots from them in the past that were easily the best auto shots I have ever had.
The best trick with any coffee machine is fresh coffee and some tweaking of the settings (fine grind, biggest dose, less water volume is a good place to start).
Grab some good beans (BeanBay brown is good ;) ) and go and visit the sellers. If you can make a good coffee on your own machine then visiting the seller with the same coffee and asking them to make you a coffee would be a great starting place I would think.
Of course if you really want to make dad proud just start roasting coffee for him and his customers!