I checked a few websites to understand what is meant by having 135/125W output and use only 60/55W. What wattage is the stock bulbs? If it's the same, then there is no problem. If you check this link,
http://www.prolightstar.com/lightbulbs/piaa_15224.html
it says that they give off enough light as if you would be using 135/125W.
BUT, before you go buy those bulbs, please read with pleasure the following link and weep!!! Stock bulbs beat those and other bulbs.
http://www.overboost.com/story.asp?id=102
Have fun.