HankBuck, my opinion is of course of little importance, but is formed from many years experience managing a manufacturing facility. We ran into many, many problems with employees who should not have been confused by simple metric conversions, but were. When we decided to eliminate all imperial measurements from our manufacturing processes, the errors mostly went away. Even then we had a couple employees who insisted on using pounds and ounces instead of kgs because it was simple to switch the display on digital scales. They said they were confused by metric measurements and they would make fewer errors by using familiar units, not metric. But a few errors kept cropping up, and were only eliminated when the old measurements were thoroughly and completely banned.
Of course, that's a different situation than an individual navigating the baggage regs of an airline. Your measurements of choice are your business. But ALL airlines in the world except the USA list their restrictions in Metric units, not Imperial. All airline employees except the USA are trained in, and use metric. All their scales and measurement units are metric. Explaining a discrepancy by saying your luggage is under an imperial unit maximum of pounds or inches is not comprehensible to people who have not used Imperial measurements. It's just friendly advice, hope it helps someone!