Again not on a Defender but I have been running them on my RTV ute for the last couple of sets. I have found them to be a bit vulnerable to punctures when down to 25% legal tread but they provide a very good grip in wet and dry, better than the factory road based tyres.
They are also no noisier than the factory Goodyear Cargos

Pretty happy with mine and will continue to buy them for the RTV. Getting about 60,000Km from a set which is a bit less than the cargos which went to 80K.

I considered them for the Defender but ended up going for Hankook Dynapro muddies on the Zu rims in 265/75-16 as my use cases were mostly dirt road work. The Hankooks have been a pleasant surprise after the factory MTRs, quieter and a better ride.

Hope this is useful.

Regards,
Tote