I don't know much about them as I've never had one.. but Sorento's were very popular for a while on the caravan circuit, I know several folks who have had them, but only one still does .... I don't fully know why but the bad bits I remember are :
One guy went through 3 turbos very quickly, seems that once one goes it keeps chewing them for a pastime, he now uses a Honda CRV.
There have been several occasions where, after dragging themselves and their vans out of muddy fields, that folks could not get out of "low/4 WD" without going through some long winded reset procedure. Luckily, on one occasion where someone completely blocked the gateway there was someone else who knew the procedure and we could then all go home with calling the rescue truck ....
The guy who still has one .. 56 plate I think .. has had a LARGE amount of welding done to the rear chassis, including a complete new cross member due to corrosion, he only still has it due to the money he has spent on it .....
On the field they appear capable enough, but seem to have the turning circle of the QE2, and are very sensitive to having decent tyres in order not to get stuck, on a couple of occasions I know of a Disco (with good off-road tyres) having to pull one guy out as he refused to buy off-road tyres .... he now also has a CRV, but still won't buy proper tyres for it.
HTH a little