Should I ditch my new Surface Pro 3 or get it looked at?

A month ago i bought on Amazon an unopened, unused but 1 year old warehouse-stored Surface Pro 3 i5 128gb as my main computer and am bitterly disappointed with it, especially as it cost me a lot of money. I'm sure the build quality is amazing, but the software lets me down badly all the time. My files regularly disappear from the desktop and today several precious pdf's of sheet music were randomly and permanently deleted without trace (not in recycle bin even). It sometimes freezes, the wifi on internet explorer often doesn't connect and the OS is terribly unintuitive and hard to use. I'm longing for the old windows XP simplicity and reliability. I've checked for viruses but that doesn't seem to be an issue so i can only presume it is a Windows or hardware problem. I bought a large windows tablet for 3 reasons: 1. It's large enough to read sheet music (ipads and samsung tabs are not quite big enough) 2. So i could get an excellent free word processor that can cope with photos and lots of formatting (i use libreoffice which is superb) and 3. Fast web browsing.
Should i pay for a specialist to check my surface pro for faults or should i just cut my losses, sell it second hand and just buy a smaller ipad and hope the word processor apps are good enough in the app store?

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