I used CentOS for years on a desktop with no problems. The idea that RHEL is only for servers is nonsense — they encourage people to use it on everything, since they obviously want to sell to as many people as possible. CentOS is hosted by Red Hat and supervised by RH staff, probably because they get a lot of useful feedback from professionals using it in internet companies and universities, so it only differs in the omission of a few proprietary items. At CERN, CentOS is used on everything, including laptops. There are two advantages to using CentOS if you are looking to an IT career. CentOS/RHEL are major players in the market and, at server level, they are almost the same as the other big name — SUSE; both, unlike Debian, use the Standard Linux Base.
For software not in RHEL, there are other repositories available:
Repositories
Stick to the approved list and all will be well.
