My personal thoughts on the jacket are to simply think of it in terms of their tux counterpoints. Tuxes come in three basic styles and all are based on lapel.
They are shawl, notch and peak. So the comparison is:

Shawl = Brian Baru
Peak = PC
Notch = Argyle

And if you go to any tux store you will find that the vast majority are the notch style (now back in my days of tux wearing I did prefer the shawl and I do intend to get a Brian Baru at some point for that reason). The only other real difference is the shiny bits. The PC and BB both have many more bits of decorative (useless) buttons. If that floats your boat, great, but again look at the usual tux - no shiny bits at all so you're already ahead of the game with an Argyle. And if you really want the shiny bits get a Bramer jacket which is basically an Argyle with more shiny bits.

Yes PC and BB are more closely fitted, but that is a style thing. And yes they usually come with a waistcoat (vest), but you can always add one to an Argyle. So basicaly it just comes down to what style you like.

For formal events black is a must, forget the goofy colors (where would you wear that?). Tweed (though ususally more expensive) is also out, though you should have one as well (black to anything formal, tweed everywhere else).

As for how you'll be received, while I can't speak for across the pond, in the US it won't matter. I attend a lot of formal events (wife is a professional fundraiser, so we go to gala's galore). I'm usually the only kilted guy, and the largest group was 4 (including me), so franklly no one knows what kilt formal is/isn't (and all of it - including what I just said - is only opinion). As for Celtic events, you will find guys from doublets down to t-shirts with their kilts, so you can dress to what ever level you feel comfortable with.

Which brings me to fly plaids and doublets. My personal opinion is that it is these things that keep kilts as a costume in most peoples eyes. This was the fashon of the 1700s for goodness sake. If you didn't have a kilt would you go to a formal event dressed like this http://upload.wikimedia.org/wikipedi...hamadeus11.jpg

Adam