I've used Amazon.com for music downloads and merchant supplied products and have had positive experiences with both. Whenever I deal with a merchant via the website I only use those with 100% positive feedback.
I've also used their review system even when I don't order through the website. When I'm looking to purchase an item from a local or online store (I like to price comparison shop), I'll try to find product reviews before making a purchase and amazon.com is one of the first places I look.
Navigating through my account to make any changes is a tad bit difficult and logging off is even harder (especially since I don't use it that often) but not impossible.
I highly recommend Amazon.com but caution users to read those feedback scores when using amazon.com merchants.
