As you all know different 4X4's have different capabilities and are designed for different purposes. No vehicle can be perfect. It all depends what suits you and for what have you designed yr 4X4.
Yesterday i along with a friend tested our vehicles in slush/ mud. I was on my 660cc LJ 50 whose weight is around 570KG's in total. The other vehicle was a LWB jimny, 1600cc, having around 1200KG's of total weight. I know comparing these two would not be fair as jimny in most ways is a far superior veh than an old LJ 50. But for sure the light weight has to perform better in slush at least. This i experienced in one of the IJC's event last year as well. Pls see these two videos.