I have bought several cheap LED strips from IKEA and eBay and all have been great. Some come on an adhesive tape which was handy and you can cut them to length to a certain extent.
The colour changing remote control ones are fun, although the colour is made up of switching various individual coloured LED's on and off so that the wash effect is changed so they aren't as bright as the warm white ones I have.
Personally I am of the cheap and cheerful variety and wouldn't spend a lot of money on them although I'm sure others have a very different view.