Arguably it has more electronics, as it is a common rail diesel, whereas the TD5 is a unit injector type engine. I drove one almost a year ago and was highly impressed by the tractability of the engine. The anti-stall allowed it to climb a 45 slope with no feet on the pedals and backwards!!! But I feel that Landrover have effectively rolled over and shown Toyota/Nissan their soft belly in submission ;-) The 300Tdi production has stopped I believe, so there is no longer a Landrover for the developing world. I got quite excited about rumours of a new Defender 14 months ago or so, only to find it consisted of a transit engine and a new bonnet <BG>
I would have one if I lived in the UK, but for Africa.... No. For expedition use, I would be a bit worried. Our electricians here can diagnose a 1HZ engined cruiser with diagnostics consisting of an interior bulb on a bit of wire, but a durotorque (?) would have them well stumped. I am not a luddite as we also have electronic CAT equipment and Renault trucks, but only because we have good dealer backup/diagnostics and parts access. Overlanding is a bit different. Eventually I reckon bush fitters will adapt as more modern vehicles penetrate African markets, and it is happening to an extent, but I would probably be looking for as recent a Tdi300 as possible if I was in UK and looking for an overland vehicle. I guess Diesel Jim or other Landrover guys would be better placed to tell you if there are any issues with the 2.4 cropping up.