60' was light, 70' or 80' was heavy although 80' was a lot better. McEwan's 80 bob was a lovely pint in the right pub. 90 shilling I believe is pretty much McEwan's No.1 or Champion Ale and is also lovely. I've never heard of anyone buying Heavy tops although I did start my beer drinking journey in pubs on lager tops. Anyway, times change and I'm enjoying a really nice Street Life Pale Ale.