It really depends on what you want. I have two bubble lights in my xbox.
http://www.xboxcore.com/gallery/details.php?image_id=1864Bubble lights:
They blink in different sequences.
They do not have a steady burn.
They put off WAY less heat because they are made from LEDs.
Bigger.
Dimmer.
Cathode Sticks:
Burn steady.
Do not alternate blinking sequences at all.
Puts off heat.
Smaller.
Brighter.
Heat was the main thing for me. I was putting mine right beside the power supply in my xbox. So I chose a bubble light.
Check out the rest of my pics.
http://www.xboxcore.com/gallery/categories...73fb59a12fd074aEDIT: I bought my 6.6 inch Bubble lights off Ebay for about $4. Shipping bumped it up to about $12 though.