I don't have any experience with the Line 6 however,I do own the Hartke 3500 which I bought back in 2005 and give it strong accolades. Very dependable and you can dial in the exact tone for your personal taste.
never played a line 6 but ive been playing every weekend with my 3500 since 2003 or 2004 and it has yet to give me any issues.
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