The first generation Kia Sorento was a very popular tow car with caravanners, it was relatively cheap and could tow 2.5 tons and reliability was good. Below is a video review from Practical Caravan on the second generation Kia Sorento.
One of the first important things to note is this second generation car is its much lighter than the previous generation. Kia will have done this for two reasons, first to improve the MPG figures but also to get the CO2 figures down because of the new Tax bands. However as a tow car this is not going to please many people as you need sufficient weight for stability. In the review Practical Caravan found the Kia Sorento to be less stable in the lane change tests at motorway speeds. Apparently owners have reported that stability is improved with the optional self levelling suspension, however its unclear if that makes it comparable to the old Kia Sorento.
The reviewer does praise the engine for its increased power output and higher MPG figure. The manual car can take 100 kg nose weight on the tow ball, but that does drop to 80 kg if you choose the automatic. You still get 7 seats and there is a lot of room in the cabin.
The final view from Practical Caravan is that as an overall car it is improved, and with self levelling suspension can be a reasonable tow car.