It is true that tablets gobble power compared to a Kindle but my Galaxy Tab lasts about 10 hours between charges so it isn't a major headache.
The weight with its protective case on is just too high to be comfortably held for long periods of time so I just prop the Tab up on my lap where it is much more comfortable than doing the same with a laptop. I'm using the Tab to make this post.
The tablet's screen is very bright and clear. When reading in low light conditions I turn the brightness down to be kinder to my eyes.
If a device is only to be used for reading then I would suggest getting a conventional Kindle. For web browsing, playing games etc., a tablet is better, but the Kindle Fire is not necessarily the best buy so shop around. You can get a free Kindle reader app for almost all devices from Amazon.
One warning though - my Tab is useless outdoors in bright sunlight and I imagine most tablets are. That's when a conventional Kindle is really the best choice.
