It's not too bad in terms of performance but for the price it normally retails at I would expect at least the Intel® Core™ m5-6Y54 Processor.

You won't get a Surface Pro for this price, I'm thinking of this although apparently Keyboard isn't the best.

For what it's worth, i think the Samsung with this relatively low end cpu/memory/SSD spec looks good value at £449. At launch it was arguably overpriced but it still managed to obtain generally favourable reviews. It's a quality piece of kit and unless you are a power user with demanding requirements, the spec is plenty sufficient for most folk. If i had a choice between a similar spec Surface 4 incl. type cover at the same price, then i'd go for a Surface 4 if only for the pleasure of admiring its looks and build quality. However, i don't think it worth the £150 ish (?) extra required, so at this point in time, it would be the Samsung for me.

I think Surface Pro 4 will hold its value much better than the Samsung

Do you just mean windows 10 in general? Or have you had a better experience on another machine.

Ive got a cheap linx tab and absolutely hate the UI in desktop and tablet mode.

Windows 8 & 10 has been putting me off buying a laptop for quite a while now.

XP was a downgrade from Windows 2000 in terms of stability but did get better after a few years and Service Packs.
I think in many ways Windows 7 is their pinnacle although I use 8.1 for various reasons it's still a bit of a hodgepodge.
XP was great compared to the joke that was Windows 9x but for those that used Windows NT it's been a downhill ride post Windows 2000.