I used Fast Fret before, but as Schmange said, its only really necessary if your guitar is newer or you don't play often enough to keep it slick. Once you get your natural finger oils on the neck, its better than anything you'd ever buy. I don't think I'd like something thats sprayed on though, seems it would get all over or too concentrated in some spots, an overly oiled neck would not be cool.
"During this line, the kid acted like he was pushing buttons on a calculator in the air. The kid played ******* air-calculator!"
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