I've never had a problem with controllers, since they basically haven't changed since 1997, and even then that was just a modified version of the SNES controller. If you've been playing games since the 1990s you shouldn't have a problem IMO. The very low rate of change since the PS1 twin-analog pad speaks to it's versatility, there simply hasn't been a need to change it. Even the Gamecube controller was just a less-effective version of the PS1 controller. X-Box originally based it's controller on the Dreamcast one but everyone complained and what do you know, they re-designed it based on the PS controller and it's stayed that way ever since.

Keyboards and me don't work very well for most games, other than MMOs or real-time strategy games where reflexes are less important and you have more abilities and options. Either there is too many buttons to remember which ones does what or you can't move your fingers to the correct key in time and/or accidentally hit the wrong one next to it, it's too hard for me to do without looking down at the keys and making sure I go to the right one, as opposed to simply doing it reflexively by feel the way controllers work. A lot of people prefer them for fps games though, I can go either way as they both have pros and cons. The best aspect of the keyboard for me is the ability to recall a specific weapon/ability through the number pad as opposed to cycling through your inventory on controllers, which can often take long enough to lead to your death when you need a split-second switch.