One point often missed about the half mil charts is that the 'shape' of the towns is remarkably accurate and seem to be easier to recognise that the more detailed town areas on the quarter mil charts.
Unless things have changed over the last couple of years, be aware that the half mil charts often stop at 7,000 feet. I had chance to come a cropper on this flying back from Jersey once when I entered an airway at 7,500 feet that wasn't shown on the chart.
Microlights, low and slow, are best with quarter mil chart, otherwise half mil is the one to use.