That is interesting. But using RadioGroup would not deviate from this since RadioGroup buttons would also be marked from 1 to 5.
Now using of RadioGroup also has another possible advantage. And that is giving you an option to make whole game being controllable by just mouse or perhaps even through touch screen interface (not sure how good is support for these in Lazarus). Modern Delphi versions provide touch support right from the start without any additional code necessary (that is unless you are interested in special.gestures).
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