First, I want to thank-you for this question and thank everyone who has already answered. I must say that the answers provided so far are very validating for me as it tends to take me hours to write hubs. It is also because of that I tend to get burned out for a while and need breaks. Then, after I write a hub, I sometimes pour over it tweaking it.
Overall, I agree that the time does not matter as much as quality and personal satisfaction that you feel it is complete. Things just take the time that they take, and that can be different for everyone.
In addition, there are also a lot of factors that affect how long it takes to write a hub such as typing speed ability, interruptions, research, correct placement of items, gathering links, how well you know the topic, your atmosphere, and even your mood. So, with that, relax, take your time (it's not a race after all), and enjoy!