Phil Truin's Super-Size free range chickens are winning prizes for taste but only if you are prepared to pay £30 a bird. I have three pretty hefty ones in my garden that are hand-fed so I might get a few more, but if you want to buy one they're here
http://www.natoora.co.uk/blog/2011/03/in-the-press-phill-truin-free-range-chicken/