If that can be useful to someone, my personal "slim fit shirts" chart, limited to UK brands as they are my favourite, (1 being the slimmer-fitting) is:
Hawes & Curtis Slim Fit
John Francombe (Lewin)
TM Lewin Slim Fit
Tyrwhitt Slim Fit
These are my favourite brands as they're the best quality for the price (honestly I'm not interested in any RTW shirt retailing at more than 60-70 EUR, as with that price you can have them bespoke in Milan...).
However I am really skinny (176 cm, 54 Kg) and H&C Slim Fit is the only line among all these which fits like a glove and does not require alterations.
TM Lewin slimmer lines fit good on chest and waist, but sleeves tend to be a bit wider! But since they offer the best quality among those brands in terms of cloth richness and cut, I tend to prefer Lewin as a "compromise" (H&C is slimmer but the fabric feels a bit cheap to me!)
Edited by Colin Maillard - 11/8/13 at 12:41pm