LR3 without question. I just got rid of my 01 disco for the LR3 and it's night and day. The LR3 has at least twice the power, runs a lot better and has about 10 times the person room in the cabin.
Secondly NEVER EVER buy an 03's Disco, most of them have a tragic non-repairable oil pump issue, and the other half that LR claims don't are having it as well. A 2003 without a new motor is a ticking time bomb, it's not "if" it's "when."
Now onto the other years, say you want an 02' or 04' Disco you're going to need head gaskets if they have not been done, and you might need them again if they have. The front drive shaft if it's factory has to go right away. Driving a disco with the OEM front prop shaft is like driving a 944 with an old timing belt.
On and on after that the Disco 2's have issue upon issue you will have to address in time. The shuttle valve issue, SLABS failure, air suspension problems, front cover seals, power steering pumps that never stop leaking, and on and on. I own a $600 computer called a "Hawkeye" just to bleed Disco 2 brakes, it really can't be done correctly any other way. (If you need it I rent it out on the forum listed below)
The best guide to buying a used dicso is at:
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