Good thoughts... You're right on all (but one little one), but I'll tell you why I got to where I am, maybe it will make more sense why I got it.
Last oil change (last weekend) I noticed tiny metal particles in the oil (verified with a magnet). While I'm certain that SOME are normal, I'm equally certain that removing THE MOST POSSIBLE from the oil stream can't be a bad thing. I was aware of magnetic oil plugs, and was going to get one of those, and searched threads just to see what people had to say. When I did that, I came across the FilterMag.
I went to the FilterMag web site and was impressed, and for the $35 thought it would be worth a shot... small investment for an otherwise positive potential payback. Then I decided to order the plug for $8 as well, to see what if anything it would catch given how miraculously the Mag is supposed to work... plus the additional benefit of a second magnet pulling shavings out of the stream.
So putting that together with what you are telling me about the direction of the flow, it IS very possible the plug will catch some before it goes to the filter, and I already have the intention of cutting open the next filter just to see how much if anything was caught there. No, I won't do that every time, but no doubt the curiosity will prompt me to do it at least once.
And in the end, I know I'm pulling as MUCH AS POSSIBLE out of the stream. You can never go wrong with keeping your oil as clean as you can... but over and above that, I appreciate everything that I get out of this forum so much that I don't mind being the guinea pig so I can let other people know what this is all about, whether it works, and whether I think it's worth it.
The one thing you were a little off on, is that it is a half circle in shape, about two inches wide, and the entire length and width of it is rare-earth magnet. It mounts around the side, on the bottom of the filter. Ideally, if gravity plays any role at all, the magnet is right there, and takes up almost the entire lower half of the filter.
The official review will follow in another 3,500KM!!! At worst, another month...
75 lbs of pull force...
