This is just too silly. It’s not even comparable to “Should I have the chicken or the steak?” And throwing in Ireland as a third option doesn’t make it any better.
Of course, if you asked me, I’d probably be doing as aggressive a sales job as I could on Paris, but then I was never much of a London fan after living there in the 80’s. I also have lived/worked/studied in Paris for years, so it’s more home to me than many places in the States. Still, to each his or her own, and I can understand the UK Capitol’s charm to real Anglophiles, or even to those preferring an English-speaking holiday. There is really no objective standard to compare the two to each other, but still, on museums, food, subway, weather, and just about anything else, I’ll take Paris.