Tried it out a couple days ago, and it's not that indestructible now. 4-5 rounds of T-90A 2006 obj AP rounds will kill the Chally 2, the gun can be easily knocked out, and a single shot to the rear side armour of the tank will destroy the vic at times. Which makes sense realistically, considering how tough the tank is with that Dorchester\Chobham.
Edit: Also to add, the quality of the texture on Burnes' Challenger 2's is pretty bad, or at least the latest I downloaded and tried out. Paint seems dull and like paste, and the interior isn't textured. Luckily, the AGM requirement has been removed.
Really a damn shame that Burnes' lost his modding file for this tank, loved it when it initially came out.