Tracked vehicles are awesome, but they experience very high wear and tear on roads and need massive amounts of maintenance. Unless you have some experience with them, you will be surprised at how little driving you get to do and how much work is needed to keep them operational. Costs are phenomenal.
Wheeled armour is slightly better, but still needs a lot of maintenance.
For my money, I would (and did!) go for a Saracen. They are reasonably well behaved and are easy enough to drive on the road. Spare parts are both available and affordable and, as a bonus, you can seat 11-12 people in it.
Cheers,
Terry