It all depends on your experience and what you are used to. I have no doubt that imperial is difficult for those who grew up with metric but the same is true the other way around. I use the metric system for several things such as distances when shooting but that is about it. For mechanical things it is much easier for me to deal with and use the imperial system on a day to day basis.

I think the metric system is great.....IF you grew up with it. For people that have spent 50+ years with inches, pounds and gallons, the Metric system isn't so easy to switch over to and live with.

That's likely true for a lot of people. While I have no problem living with both systems on a daily basis, my wife constantly asks me to convert metric weights and distances into the 'old' measurments for her. And I still don't even try to figure out European engines rated in kW instead of horsepower.

Kw to HP is easy - just multiply by 1.33, or add a third again e.g. 225 Kw x 1.33 = 300 hp. It's not exact, but close enough. I grew up with both imperial and metric and find some stuff easier in one system and other stuff in the other e.g. I automatically know 150 mph is pretty fast, but 180 km/h I would convert back to get a feel for it (112 mph). Lifting weights I know a 500 lbs bench is awesome but if someone said they lifted 190 kg I would automatically convert to lbs to know if it was good or not. Engine measurements I find very confusing, fractions of inches especially. Metric is so simple in comparison - I have a chart on my wall with all the metric and imperial spanner sizes. If a socket is too small I don't immediately know a 3/8 socket is bigger or smaller than a 5/16 without doing the math first (6/16 v 5/16). As for 0.040" etc, makes my brain ache.

If you can sum 1 and 1 bingo you can use metric, no such thing as foot, inches, gallons etc, why you find it so complicated too use it? 1 +1 = 2 , 1 centimeter + 1 centimeters = 2 centimeters, you get 100 centimeters is one meter and so on and so forth same with liters and kilograms1 + 1 = 2 , no fractions,

They tried telling us that back in the 70's and I was in 6th grade. It's soooo easy, everything is multiples of 1 or 10 or 100. Thing is, all of a sudden it never happened here. Although, I just noticed the other day the aftermarket battery cables are 13mm....?!?

Exactly my point, let's cut the crap ok guys, we ALL use both systems in our daily lives, why are we here and I mean this forum? We all own a b body, and like to work in our own cars Right? Wellthat meant that we are all mechanic inclined, and I admit I do own both a metric and an Imperial set of dice and sockets if a freaking bolt is rounded one or the other will do the job to remove it, after 19 mm I know I have to use imperial measurements is easier that way, below 10mm is easier with metrica, if I want to buy pipes, again I use us system, same for wood, but goes the other way around if you or I am thirsty I buy half a liter or a liter of water, you do not buy a gallon or a us gallon or an Imperial gallon to drink water is easier in liters i have buy liters of water in the us, but if I buy a can of engine oil what they sell me is not a liter is a pint of oil and here only a few knows that here, and so on and so forth, as you can see is a mix and match of measurements and systems in our daily lives, deal with it.

There is a good reason that long ago- surveyors tossed inches as a way to break down feet- and went with tenths and hundredths of a foot for calculating ease. Engineers did the same thing with inches when they adopted hundredths/tenths/thousandths of an inch. In my work over forty years with dealing with detailed blueprints in machinery and building construction, I have only encountered "fractions" of feet and inches being used when I was reviewing original documents from very old construction. --Metric/base ten- is old and reliable for minimizing calculation errors. My go-to conversion is one inch equals 25.4000 millimeters. This conversion is true to within a couple of thousands of an inch over a hundred feet plus. My point is that base ten calculating is what metric is all about. --Example question-- How many feet = 429/27s of an inch?--Hint it's a rhetorical question.

What reference of measuring was used to compare feet with chains? --What portion of a foot would equal one link in a "chain"? Something clearly happened with measuring stuff long ago.--Base ten happened -and reference standards are in place. -Good-by fractions of someone's old foot and all the chains that may have been attached to them.