Been thinking, tdv8

Is it best to buy one at 50-60k miles or 80-90k miles

I would jump in and say always buy the lowest mileage for your budget, but, would the higher mile ones have all the expensive stuff that goes wrong done?

I bought my TDV8 in March this year with 52k. So not much time in which to answer your question fully. However I already have issues with the headlights which, at dealer prices, would cost over £2000 to fix! Using an auction site to purchase would bring that down to £400-£500.
My thought was that the lower mileage would give, what should be a really tough vehicle, plenty of miles before anything major occurred. However reading this forum is a worrying thing as there seems to be no rhyme or reason to issues arising. My one had replacement anti roll bar bushes fitted by the seller, and a new battery as part of their vehicle check before I bought it!
One thing you should perhaps be asking at the same time as asking about mileage, is what year is best? Different modifications and changes by LR over time may impact your decision.
Hope this helps and I am sure others with greater time with their beasts will provide more detail. Robin
2008 Range Rover Sport TDV8
Gone:
Jaguar S-Type V8 4.2 Sport
MGZTT 190 2.5

I've always bought my cars on mileage, especially the last 4! All m3's

Also I've noticed some have the mouldings all around the bottom colour coded and some not, is this an extra or an edition?

The TDV8 has its issues - notably with the turbos. However, it's not so much age as care that matters. They seem to prefer to be used rather than do short journeys. Taking care to let the turbos spool down before switching off seems to help too.

As for other bits, suspension bushes are consumable items on all RRS so just expect, at some point, to need to replace some. ARB bushes are particularly prone to wear.

AFS headlights seem to be causing a few issues but whether this is a batch problem or the beginning of a new "they all do that" problem is yet to be determined.

Don't discount high miles if done in long journeys. A high mile motorway cruiser will be in better health generally than a driveway queen that does 10 miles a week dropping the kids at school. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed