things to watch out for on the TD5 are fuel pump, normally packs in around 100,000 or so, just ask before you buy if you are keen has the fuel pump been done...the tdi300, are less powerfull, and a little bit more hard to run than the td5,
Make sure the centre bushing above the back axle is in good nick or it'll handle like a cart on the road.. i've had very little bother with the td5, since buying it, but its well looked after, oil change, every 8000 miles.....they are comfortable on road, as well as off, and just make sure body etc is in good nick also.
ps. theres 2 in the family on