While I'm not normally partial to the Metric/Imperial debates that seem to exist South, or even online - often the hassle of swapping from a familiar to a less so system of measures is going to cost more effort than a more efficient system might gain - within coffee is one field where the use of metric measures is so much easier that I will still advocate it.
Quite simply, if you have a scale that can do Metric, you don't need to understand or have an intuitive grasp of it; much less conversions or translations between. And using metric while brewing coffee is so particularly simple that it's worth prioritizing a scale that at least has a metric option.
Using metric weights and fluid measures (grams and millilitres, respectively) for beans and water makes for very easy brewing math, because the two convert 1:1, a millilitre of water is by definition the volume that makes up one gram. When someone gives you a brew ratio of 1:17, metric is fairly easy to scale. Multiply both sides by the amount of coffee to be used, (For 20 grams beans: 20x1=20g coffee, 17x20=340ml water) or divide your water by 17. Even if you're more familiar with Imperial measures, the intuitive scalability of 0.71 solid ounces of coffee per .574 fluid ounces or .84 cups of water doesn't translate as elegantly as "1:17."