Halfcrowns are my favourite UK denomination! I particularly like the shield designs of Edward VII, George V and George VI. I have a fair number of them (at least 1 of each date in EF or better from 1910 to 1967, the 1930 being aEF). I never tire of them ... I long for the day I can get a 1905 in any condition ...
They are nice, Thats some collection you have there. They are a lot easier on the wallet to collect than full crowns.
This one has seen a bit of use in it's almost 200 years: Great Britain Half Crown 1817 - King George III