UK Dialogue

I've just come up with an attempt at a short (750 words, I think) humorous tale -- probably for Fictioneer, since it's non-TG and there's only been one story posted there by anyone in more than 10 weeks.

But it seems slightly more appropriate for me to set it in England than the U.S. Because of that, I'd appreciate a reader from that side of the pond letting me know if the dialogue is too American. (Now that I think about it, I don't even know if the payoff sentence is used there.)

One other question: the story revolves around a visit to an independent genetics laboratory by someone with the power to cite the owner. It's written right now as a police inspector, but I assume there'd be a more appropriate civil authority of some sort (environment? health? something more specific?)

Anyway, if someone's game for it, please let me know and I'll send it to them.

Thanks, Eric