I think SurreyJohn has covered most of it.
To answer your earlier question, yes 3.1 Bar is 45 PSI:
https://www.onlineconversion.com/pressure.htm
I would agree with John, running them harder is probably going to be a false economy because they're likely to wear out the centre of the tyre before they wear the rest of the tread area, so you'll be throwing them away earlier, and they ain't cheap!
Is yours a 4x4 version? If so, swapping the tyres round to even out the wear is even more important.
We made (a pretty painful!) investment in a set of Winter tyres and I bought another set of second hand rims over a period of time on eBay, so we can swap them from one season to the other. I can certainly vouch for the improvement in cold weather grip - not just snow and ice, but even just in the wet as the temperature drops below about 3 or4 degree, I can feel an improvement in stopping and cornering ability. Supposedly, they start showing an improvement below about 7 degrees, but I can't say I've noticed it at those temperatures. We'll swap back to the "summer" ones at the end of this month. Beware, there's a lot of half-truth and misinformation about "winter" tyres. Some manufacturers sell "mud-and-snow" tyres, which are NOT the same thing! A true winter tyre will have a three-peaked mountain symbol with a snowflake in it:
if they don't have that, they don't meet the legal requirements to be a winter tyre - regardless of what's written on the sidewall! Some all-season tyres can just about meet the winter tyre requirements, so they qualify for the symbol, others can't, so it's worth checking, and don't be fobbed off with any spiel about "mud & snow"! (That really only refers to the tread pattern).
Lastly, don't be worried about tyres "bursting" if you run them at a higher pressure (obviously, within the limit marked on the sidewall)! under-inflated tyres are at greater risk of that. It's really only uneven wear that will be a problem.