Well, just driven a set of Mudzillas on the road, first impressions pretty good. None of the "Avon Ranger" steering feel that you get with many crossplies, and also with the Insa Turbo Special Tracks - the steering feels as good as with a good wide radial MT. Bit of an odd resonant noise at about 20mph but that aside, they are no more noisy than most wide mud-terrains like BFG etc, noisier than my 265 BFGs but not really much different to the 12.50s.
They are definitely about an inch undersize in both directions as the "33x13.50-15" size is only the same height as my 265/75R16 BFG's, i.e. about 32 inches, and they are only the same width (tread and section) as 12.50 tyres of other makes.
On a set of 10x15 rims they do achieve the "fat boy look" though - mine are going on 8x15s because I don't want to look like an 80's Vitara
Need to get mine fitted and then we need some rain