I've also had good experience with the Kendas, 18 months on two bikes with no punctures and the wear rate seemed low.Yep all slimed up and with the Dodgy Kenda tyres! I still think they are brilliant!
I'm not so supportive of the slime though, as Mussels found, when it lets you down as it so often does, a puncture can be nigh on impossible to repair out on the road once that sticky fluid spreads over the tube surface.
I've tried Slime and alternatives and have never had any success, so I believe that should be a customer choice item rather than standard. If supplied as standard the first thing I'd do is change both tubes.
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