My EFS kit has been on for 3 years now, 15,000 miles as the 80 only does just over 5k a year.
The springs are showing quite a few signs of rust and the rear shocks are looking very sad indeed, the paint has completely come off the lower sections.
The kit didn't really improve the ride on the corrugations in Morocco so I'm thinking of going down the Reiger route for shocks, not cheap but come highly recommended.