Also regarding Kiton vs Formosa - as Greg said, Kiton makes a lovely jacket, but not only is the Formosa made in a smaller workshop, it also has more handwork than Kiton. For instance, Kiton uses machine-padded collar and lapels.
I think he means this one:http://www.nomanwalksalone.com/index.php/clothing/sport-coats/green-brown-madras-check-linen-silk-sport-coat.htmlIf you're not logged in as a Founder's Circle member, the code SF10JUN should give you 10% off. You can check @gdl203's signature for the current code in the future.
Another word about cloth - Kiton bought the famed Carlo Barbera mill, so I would assume most of their fabrics come from this Italian mill. I don't know what Brioni's fabric sources are, but I would guess Italian. Zegna of course uses its own mills.
Tailors, even in Naples, still prefer to work with English cloth because the additional body in the cloth allows it to drape and hold its shape better. Gennaro Formosa particularly likes Holland and Sherry, and for good reason...
The NMWA Formosas and Brioni have hand-padded lapels, but Kiton uses machine-stitched canvas.
NMWA has some models in a spalla camicia, some in a more classic soft shoulder.
I think Kiton also has various shoulder styles.
Kiton also has different silhouettes - they make a cut for the American market that's more generous and, to my eye, sack-like.
The other difference is cloth....
I have a couple of Valstarinos - if you want that classic looser look of the A1, I'd size up. Or if you're planning on wearing a sweater underneath. If you want slimmer, take your normal size. Just my 2c.
The thing that works about them is that while everyone looks worse in them, if you've got any extra weight on you, you'll look WAY worse. So if you can carry it off at all, it proves that you're young and skinny. Many a trend has achieved success based its ability to differentiate its adopters in this fashion.