Both of the upgrades below were long overdue, for us. We have 45,000 miles on our Europa and finally decided to take the leap.
National Seating SK-582-10 HP III SHOCK KIT: The seat shocks compliment the ones already installed by the factory. They significantly reduce the amount of air needed to eliminate bottoming out on bad roads. Since the seat no longer needs to be raised as high it allows for better visibility out the window. They also reduce the bounce in the air seats that I always found a little anoying.
99B-3209 FRONT KONI EVO SHOCK: The stock Sachs shocks never were great but after 45,000 miles they just weren't cutting it any more so I installed the Koni EVOs.
The installation for the seat shocks and the Kona EVOs took me about an hour. After the installation I went for a test drive seeking out pot holes and rough bridge transitions/dips and the improvements are even better than expected.