Even though RangeRover is much superior to Land rover defender still it cant be used for hardcore off roading.
if it will go for sale price will be well above rest of the market and int he 80-90 lakhs. eventually attracting very little market.
where as defender will be attracting buyers from landcruiser and pajero ranges ( base models off course)
To be honest there is no offroader like landrover defender, it is rough and tough and made for off roading.