Last suggestion; consider a less detailed model for the walkthrough - most people won't notice the small details unless you point it out to them, there's too many elements to process. For the extreme details, static will always work better - the feeling of having to rush through and see everything isn't there - I mean it's called a walkthrough for a reason. You could probably present the walkthrough, point out scenes that they should take note of, then follow up with static shots depending on the client and their interest. Just a few thoughts to think about!