Getting my 350 rebuilt this week, already ordered a test kit from Blackstone labs to send them an oil sample at my first 3k mile oil change, but I'm also wondering if I should pick up a Filtermag SS300 for my oil filter? Wondering if they are actually helpful, or just a gimmick. Friend of mine says most of the harmful stuff in the oil isn't magnetic, so it won't help that much. Other people (like my boss) swear by them. Not sure who to believe