ROS is definitely the way to go. Aside from the plethora of existing libraries for preexisting robots, its the 'industry-standard' for personal robots. Plus, its really quite easy to learn, well-documented and capable of really impressive things.

I have had nothing but problems with ROS. I've tried it with Lego Mindstorms and with a Turtlebot. Both experiences were painful beyond words.

I think the problems with ROS stem from two things:

1) Complexity - way too much complexity for the really simple stuff

2) Change - code samples and documentation you find on the web don't always work when you think they should. I've wasted hours getting simple stuff to work.

I strongly suggestion you think about why you need a robotics OS. If all you want is a library to move motors around, you don't need ROS or anything fancy. You don't need it if you just want to interface with a Kinect. Just use individual libraries and write the glue code.

In Short: It depends on your project.

That being said, you might want to try out these other middlewares: http://www.mira-project.org/joomla-mira/ , http://plasmodic.github.io/ecto/

Do you have a local "hacker space"? They would be good people to chat with about this kind of thing.