In reply to David55:
You would 'enjoy' yourself a more on a £2000+ bike no doubt ... unless you just are pootling along gravel double track.
The main advantages gained from better forks, better brakes, lighter wheels, better tyres.... and (usually) more refined bike geometry (which can/will make a huge difference).
I've seen this transformation with riding friends countless times when they go from a entry-level and/or old bike to something modern low/slack in mid range or above. Their grins say it all.
The notion you alluded to that anything bar the cheapest kit is all a 'gimmick' is frankly bolx. For sure, it may not be a linear cost to improvement graph and the cost of the top-top end stuff really does makes your eyes water (and the wallet bleed), but top end less one or two notches is often a good sweet spot.
But if mountain biking is just a simple utility equation of number of riding days for minimum cost, then that's fine if that's what you want, but its not the way I look at things or want out of MTBing: fun per ride out with my mates is the key for me.
And sometimes, its just nice to have a bit a bling, especially if it's your main thing. And there's is nothing wrong in that.