Ran same mousse for 3 years without re-greasing - got a bit 'soft' at the end, but didn't break-up. Only removed it when i changed tyre. @Hoots - i would run one in the front of a 950SE, but a heavier bike may reduce the life of the mousse significantly. Might be ok for a dedicated hard-core ADV ride on a 990, but i think long/high-speed gravel/sealed runs would not be good for said mousse on a bigger/heavier bike. Correct rim size (width), matching tyre and mousse is important to prevent premature failure too. There are now a few more mousse options than when i started using them. I used Michelin tyres/mousses. No science or data mate, just my deductions from where I've witnessed successful and not so successful mousse experiences.