I actually went to Littlehampton rather than any of the other south coast seaside towns because I'd seen this cafe, and I wasn't disappointed.
The design was as interesting as the photos suggested, and presented some good photo opportunities. (Though, given the weather here in the UK this Jan/Feb, I was extremely lucky to pick a sunny day).
The food was good, certainly above what you'd traditionally think of as cafe quality. Prices were also a little above cafe prices, but in keeping with the quality.
I actually stopped for coffee and a cake, then later returned for a quick lunch. The inside was cosy and warm despite it being a very chilly and windy day, and getting a window seat just made the experience as good as you could expect!
Will definitely return if I'm in the area again, but I suspect, given that it was over half full in winter, that it'll be totally full in the summer.