On the other hand, I wonder how quickly it'll become annoying. If you have more than a few of these products, getting badgered to update your review every year for each of them might get tedious. Perhaps gamification and/or some other sort of incentive could help, but I'm not sure.
Also, if I've had something for 5 years and it's still going strong, I doubt I'll be able to add much new info at year 6 - unless it broke down of course. So perhaps decreasing the frequency of reviews slowly over time would be useful. Perhaps something Fibonacci based, so you'd review after year 1, 2, 3, 5, 8, 13,...