I've come to the conclusion custom (really, really custom)-painted bikes like the Dawes you flagged, Andy, are a bit like tattoos -- highly personalized and with great meaning to the owner, but of limited appeal to the general population (perhaps because they are so personal!). Commissioned art is like that.
At first glance, the thumbnails really put me off the color combos on the Dawes, but when I enlarged the shots and could see the details, it sort of came alive for me. Painting bikes involves a lot beyond mere color selection. Among the challenges is making something that looks good at a distance versus something really meant to be seen up close, probably mostly by the rider. Bikes are mostly tubes and there's not a lot of surface area, which is why we generally see only one or two colors and panels, fades, and cue-stick paint jobs.
Sometimes, as in this case, the special paint jobs are made for promotional or show purposes, and are an expression of the painter and showcase a company's product. It is nice to see something different.
The eBay ad copy reads, "...it was manufactured by Dawes Cycles to promote the Dawes touring range for the Dawes annual trade show". A work of art...surely! It is quite a feat getting an entire landscape on a bike, and well done to the painter. However, something like this may have limited appeal to the buying public, perhaps accounting for the comment, "...This bike has been on display in a shop so may have a few marks". Perhaps it has been sitting awhile (I see the tires are flat). This one may have more appeal due to provenance than appearance...it does come across as a bit hand-done in way that may not be for the best. Art can be polarizing!
Contrast that with Darrell McCulloch’s Llewellyns in Pete's link; there is mass appeal -- the bikes and lugwork are so beautifully integrated as to be of a piece and the appeal is much broader -- perhaps because the paint schemes are more conventional and therefore more accessible.
Interesting what resonates with individuals and what doesn't. Five bids with 9 days to go on the Dawes; I think it'll close high. It'll be fun to see what happens....
Best,
Dan.