I would call it nearly a wash so far with the GX in terms of regular and preventative maintenance. Yes, Toyota has legendary quality, but you are still buying complex, luxury vehicle and expect to pay as such. I had a harder initial pill to swallow on the LR3 getting it caught up on maintenance vs. my GX which I bought CPO.
LR3 eats LCAs, GX electronic shocks go.
GX needed a caliper for a frozen piston, my LR3 needed a wheel bearing.
GX needs timing belts, LR3 has some weak points in the cooling system.
I've taken it up black diamond trails in the Browns Camp/Rogers Camp area and it didn't miss a beat even in wet and slippery conditions.