Compact strip light question

They should. Most 65W / 55W ballasts are identical. There is virtually very little difference or power between the two.
 
I'm thinking it's like any other lighting fixture. It's okay to run wattages below the limit, but not above. So if a fixture is rated to 65, than bulbs less than that should be just fine. In fact I've seen some fixtures online that come with 65w 10000k bulbs, but if you select a "freshwater" option, the 6700k bulbs they give you are 55w.
 
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