I would say that BVE is worth the download.
I have a few routes and a few locos but the thing that I don't like is not being able to 'look at the roof' and maybe look behind at your train or at least have other views in the cab. Also don't forget that Trainz you are supposed to be able to be the 'routemaster' so it is necessary to have a free roaming view.
Is worth the download though
Ben