I only got the Echo Dot because Amazon customer service told me I could not control my second AmazonBasics microwave with my Amazon Tap, which worked fine with my first microwave. That was incorrect. All I had to do was change my vocal command from "Alexa, two minutes microwave" to "Alexa, two minutes ON microwave." Of course, I only found that out AFTER I bought two Echo devices as a result of the conversation with Amazon.
Because Amazon had a $99 deal for Echo and Echo Dot together, I pounced. I didn't realize you needed the same Echo model to use two of them to produce stereo sound. I have two new Echo devices that cannot produce stereo sound together. With that realization, both devices lost value.
My Amazon Tap -- whose mention the Amazon customer service people found funny for some reason -- has a rechargeable battery and a charging base as well as a micro-USB port in the actual unit. I use it as a portable device throughout my house and outside. Really well-designed, portable and flexible. Both the Echo and Echo dot require a/c power, lowering further the value of both for my purposes.
The increase in sound quality between the Echo and the Dot is easily worth the price difference. I was dumb to get the Dot.
In a logical progression of a product that lost utility the longer I owned it, I dropped it, the sound stopped working (the lights responded to my vocal commands and it started the microwave though) and I threw it out. In venting my frustration with a hammer, I learned the unit is sturdy and I could only put a slight hole in it after about 10 hard whacks on a concrete floor.
I feel better now. All that stress and disappointment only cost me $29.