More aggressive and remote terrain favors the relative simplicity of an early year 100 (relative to 100-Series
); '98-'99 MY IMO. For my uses/application the additional complexity and repair costs associated with the nav and exhaust manifold air pump system (EPA) coupled with more air bags, electronics, etc., of an '06-'07 would be a a deal breaker for me. The new component costs to replace the nav unit and air pump system is over $8,000 combined. And from what I've been told by one of our esteemed Land Cruiser experts, when the exhaust air pump goes it codes out and has a similar effect as an APPS or TPS failure; not likely an in the field type repair.
I'm not sure the OEM nav unit, on an '03+ would be a complete deal breaker...but I'd certainly prefer one sans nav no question about it.
For the types of terrain I travel a front locker is not an option but a necessity...an ARB locker resolves the front diff risk. Even though '00+ years got the 4-pinion planetary gear design they have seen their fair share of front diff issues too...so for the best reliability you're looking at an ARB up front on any year 100-Series.
OTOH if your "overland" travels are less remote and rugged...and you can accept the costs/inconvenience of potentially needing to replace the nav and/or air pump system then the power of the VVTi and A750F equipped '06-'07 MYs is very compelling.
If there was an economical way to drop in the A750F 5-speed auto tranny from an '03+ into my '99 that would be flat out a near perfect 100 for me. Add OEM cloth interior and take away the sun roof and I'm 'there'
.