I say there is absolutely no rule against cuffs on flat-fronts. What’s important in this matter is the width of the garment’s legs. If the pants are cut very slim, as many designer flat-front pants ...

You can get a designer tux with at-front pants, no problem. That’s the trend. Just try to avoid looking like you’re heading to an awards show. You know—notch collar, three buttons, stripeless trousers ...