I used to buy almost everything on Amazon - electronics, books, kitchen/office/cleaning supplies, etc. Back then I was a Prime subscriber so I did not pay for the delivery. As for the delivery, it was blazing fast and the item was always in a mint condition. In case of any issues I was able to sort it out within a day or two. And the price was better than the other online or brick and mortar stores.
However, at some point the quality of the products went downhill. Support became unhelpful and the prices got higher than the competition. One time I had some issues with the order. It never got delivered and the process to get my money back was way too long and too complex. Eventually I have contacted my bank and reported the fraud. Eventually I got my money back. Turned out that such issues were not an anomaly and a lot of people reported shady sellers.
Since then I have unsubscribed from Prime and every time I found something I wanted to buy I’ve checked the seller and if there was a website I bought directly from them.
For past few years I didn’t buy a thing on Amazon.
As for the alternatives, I don’t have a single one. I have several websites I usually buy from but in general I always do some research and buy the product from the seller that has the best price and is trusted enough.