As far as I know, yes, only at The Genealogist. And yes, for map nerds it is fantastic, and it is easy to use, once you have found the locality of interest. There are map views with individual properties marked with clickable keys and that takes you to a transcript and to the images of the valuation records. Just be aware that it is still being rolled out so currently the coverage limited to the broad south east. There are regular updates however.