Another helpful and positive contribution from PopBunny!

Never used TM Lewin but very happy having ordered a couple of shirts from Charles Tyrwhitt, plus their website taught me how to tie a half windsor knot the other day. I did pop into the Jermyn St store beforehand just to find out what my measurements were and the fit of the shirts I've found very good. They do seem however to be one of those retailers whose product is ALWAYS on offer and they will bombard you with offline and online marketing if you let them.

I'm sure a BA Gold will be along soon to discredit both labels and make a suggestion based more on blowing their own sartorial trumpet than actually answering the question, but that's the BA forum!

And you could say this is on topic as both brands are sold in the BA estore