Steve Rainbird wrote:
Is there a valid reason to buy these expensive paints especially for
kitchens or are they an expensive extravagance?

I don't think they're worth the extra - they are (AFAIK) supposed
to have a vaguely anti-condensation effect, but if it's not a
problem... I'd just use ordinary emulsion/gloss, if there's an
issue it's better to fix it properly.