Those tieraps work wonders if you're gonna leave your PC as-is for a long time, but hardware dorks that take out their parts (hard drives, RAM, videocard, etc.) frequently will have to cut them out everytime. If you know that you're not gonna change out the parts anytime soon, they're perfect for the job. They improve airflow considerably.
I also give a highest recommendation to rounded IDE cables:
They're much neater and they improve airflow even more, especially when upgrading from:
-Lasereth