Sigh.

I can't believe I'm going to reply to a 10 year old thread that had an obvious answer back then.

But, for what it's worth:

My string trimmer is a light duty corded model. So of course it takes .065.. Doh. They all do.

But like a lot of string trimmers the auto feed is broken. Now, I can manually thread a bit of .065 into it, but it wears out right away. So I take a short piece of .095, tie a knot in it, and run it out one of the holes. The light duty trimmer runs fine with a piece of .095, and when it wears down too short I just stick another piece in. Yeah, it's a pain, but I only have a little trimming to do.