Never used the UK 1/4-mill charts.
But I have used the US Terminal Area charts, which are 1/4-mill. Not entirely sure that they really helped me at all compared to the Sectionals (1/2-mill), but they are a legal requirement so I used them.
Having come from an environment where I got very used to using 1/2-mill charts, I have to admit to getting confused more than once. No problem when planning a trip in advance, creating a plog and following the plog. The problem is when you just "go flying", making up the route as you go, estimating distances on the chart. Once or twice I "forgot" which chart I was using, and estimated distances as if I were using a 1/2-mill chart. Which resulted in me going twice as far as I should have gone, and then wondering why I'd overshot my intended turning point by so much.
My personal advice would be not to bother. But if you do go for them, then use them regularly, you'll only confuse yourself if you keep them for occassional use.
FFF
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