Lumpyoatmeal saidIs 180 euros the price? In US dollars that's around $202; here that would get you a crappy bike that wouldn't last at all.
Follow the advice of the posts above.
I have to agree. Over my lifetime I've never owned a bike worth less than about $3000 USD in today's money, and sometimes quite a bit more. Even when I was a little kid, thanks to Dad.
He had my first 2-wheeler imported from Belgium in 1954, a beautiful thing. He called it my "Belgian racer" because it was a smaller version of the classic diamond frame so typical now, which few US bikes of that era had. Everyone else was riding heavy, tanky old Schwinn things.
Nor did I buy my 2 sons anything less. Their first 2-wheelers were both Treks, well into 4 figures, over 20 years ago when they were preteens.
A bike is a form of personal transportation, you don't stint. No more than you would on a car. You want it to last and give good service. No cheap department store crap, you go to a proper bike shop.
I say again, if you want advice on mountain bikes, ask paulflexes, as MasterOfTheDomain has also said. Paul's our resident expert. I know road bikes, but not mountain bikes. I'm surprised he hasn't replied to this.