Just before the Fire came out, I bought a Kindle 4 non touch to travel with. I like it a lot. I loaded it with my paperwork, reading material, and local menus and it kept me busy in transit and when dining alone. I was very happy with it except, 1) it was difficult to read in dim light, and 2) it was difficult to navigate technical books with large images -- the images were simply too small to read.
I got a fire when it was available, and have not used the kindle much since. The k4 is only used when 1) reading by the pool, 2) someone is using my fire, or 3) the fire's battery is discharged.