So, I have been asked this question many times. And of course the assumption is that I am some sort of a masochist who enjoys wasting time on compiling packages. However, that is not entirely true. There are some other reasons why, after trying Ubuntu (started linux with it), Gentoo and then Arch I settled on Gentoo.
The main reasons in a nutshell would be:
1. Rolling Release – Arch does the same thing, while you could achieve the same if you keep using the development releases of Ubuntu. (However, once a feature freeze sets in, you have a wait of couple of months before new packages move into the repos). Arch, in fact, is more bleeding edge that gentoo. However, that is an advantage and a disadvantage as well. While it allows you to have the most bleeding edge system, minor breakdowns are expected. The same can be said for Gentoo – however, with the option of hard masking (not normal masking) a saner solution exists.
2. Portage – No other package management compares to it. Period. Not even the mighty and holy apt.
3. etc-update/dispatch-conf – Haven’t discovered a better way to manage configuration files in a better way in any other distribution. Very useful, if you like to edit your configuration files and do not want them to revert back with an update.
4. eselect – Modular configuration framework. In my opinion, the best feature of Gentoo.
5. Slotting – Install more than one version of the same package.
6. It forces you to learn command line – it is quite useful when you become used to it.
7. And before I forget, the famous USE flags. Trust me, once you get to know them, they are really helpful. And of course, there is no counterpart in any other distribution – this is a unique feature of gentoo (or rather source based distributions)
However, it is not that rosy. There are some disadvantages as well. The most obvious is the time consumed in compiling the packages and in getting the system installed. However, once everything is ready which would take anywhere between 3 days to a week, you would have a great system and you do not have to put in too much effort in maintaining it.
But still. only those who want to spend some time in building a system should try gentoo. Other than that, there is always Ubuntu, which is the best distribution if you are new to Linux.