Standard tyres v narrow tyres

Hello guys. I am getting close to change tyres on my Jimny I prefer to buy narrow tyres size 175/80/15 over the size 205/70/15 the diameter is within 1%. My point is that Jimny may be more economical(she`s not bad) another thing is that the car may be less bouncy also the narrow tyres cut better trough deep surface water these are the main reasons. I know about some bad points like bad cornering and little worse braking another thing is that Jimny may not pass the test(NCT here in Ireland). I`ve done some research on the internet basically it says narrow tyre is better off road and worse on road.
Has any of you put narrow tyres on your vehicle will you share your opinions? My biggest concern is that will Jimny be dangerous to drive on road(I drive 90% on road 10% off road on the farms).
Cheers

Stick with standard tyre width, 205's aren't exactly wide. With 175's I think it would drive a lot worse, would have some potentially fairly poor road holding characteristics in my opinion. If you want narrower go for 195's, slightly narrower but still wide enough to handle road driving. If I remember correctly, the JDM spec Kei Jimny has 175's, but that is rear wheel drive only and has narrower axles.

Given that in anything other than bone dry conditions it is relatively easy to spin up the back tyres in 205 section and that in the wet understeer is an ever present concern i would not be wanting narrower tyres on a Jimny. On my defender i was incumbered with 750r16 tyres because father was of the same opinion that narrower tyres are better off road, they may be in certain circumstances but not universally. If you are wanting to dig deep ruts across a field then narrow tyres are the only choice, if however you want to achieve progress without creating a mess then avoid them and get something with at least a moderate level of floatation. Oh and the defender was a liability on wet roads too. There is a lot of time and money spent on developing a reasonable compromise tyre wise by the manufacturer and if you are using the car as intended then stick with the standard size.

I think you will find that tread pattern will make more of a difference to grip and economy than
going down a size. Its all about on/off road compromise.
More aggressive pattern means more drag. My mud tyres have cost me about 10% more fuel
but are just about unstoppable offroad. A good compromise are the Yokohama Geolander in standard size.
We have these on my other halfs Jimny. Fuel use is the same as her road tyres, they work well offroad and
they ride nice on the road.

Thanks for your replies. I`ll get the standard size tyres. I was looking at the Yokohama Geolandar A/T-S and also Michelin Latitude Cross they both have very good reviews but Michelin's being dearer

I fitted Kumho KL78 195/80's road venture's....they were ok on and off road.....never went past 105MPH though so can't say if they would be OK at speed.....only changed them as they looked lost when I fitted my bodykit.