Say what you like about Amazon, but their no-quibble returns policy is second to none, even in places like Europe that have high-levels of consumer protection enshrined in law.
From my own personal experience:
Amazon: Bought an IT component on Amazon (sold by third-party, not "sold by Amazon"). Item that arrived was not as described (lower spec than promised). Filed a return on Amazon, Amazon paid for the return shipment and refunded me as soon as the courier scanned the collection barcode.
Third-party: Bought a new PC from a reputable reseller (with whom I'd dealt with before occasionally over the years). PC arrived, hardware was OK but the BIOS was completely FUBAR (corrupted beyond salvage). Requested a return and a refund. Despite consumer law being strong in my country, the seller made it so painful and was dragging out the process so much (no doubt so they could push me past the consumer law deadline) that I gave up. I now have an expensive doorstop that is completely unusable.
I still buy from third-parties, but generally only low-risk stuff or higher-risk if I've got recent prior really good experience (or if there's no choice, e.g. things that have to be bought from "authorised resellers"). Otherwise for random stuff, if Amazon stock it and its not outrageously above the going price, I'll just buy it on Amazon for the peace of mind.