I reckon you'd be happy with either, but I suppose it depends on what you want to do with it?
If you want to do a lot of towing and are concerned about fuel consumption, I'd go the CRD. If you want a great sounding, smooth and very quick 4WD that will put a smile on your face everytime you stand on the loud pedal, get the Overland.
Just remeber you can convert the V8 to LPG if you want to get better than CRD economy, but that obviously comes at a cost.
I love my V8, but would consider a CRD if I was updating or looking at another one.
Sorry to sit on the fence....