Should I add a Magnetic Oil Pan Plug or not?

Pros and Cons of adding a Magnetic Oil Pan Plug for my 2.5 liter CX-5
Strange many car makers put them in their transmission pan but not in their engine pan.
How well would a strong magnet on the outside bottom of the pan work as an option to the magnetic drain plug?
I know the magnetic flux would be dissipated by being on the outside but hard to know how much loss there would be and if it would still work.
Where to buy a good one?
Thanks

PS, I just found another option, super strong magnets that fit on the outside of the oil filter. You remove these magnets and put them on the new filter when you change the filter. I can't think of a way of using these magnets and then checking to see if they actually captured any ferrous particles. If you cut the filter up you would be putting metal shavings into the filter as you cut it. Any ideas of how to test this product?

Then there is the temperature issue.
is everyone using Neodymium-Iron-Boron magnets?
Quote Originally Posted by http://www.rare-earth-magnets.com/t-magnet-university.aspx
if you heat them beyond 170 degrees Fahrenheit (80 degrees Celsius) the magnets will begin to loose their magnetic properties. Sustaining these temperatures for a length of time or heating the magnet significantly higher than this will permanently demagnetize it. Other types of magnets such as Samarium-Cobalt have higher heat resistance.

Here is a site that specifically says they have one that fits the 2014 CX-5
http://www.magneticdrainplug.com/Automotive_Drain_Plugs/AP08.html#.Umn4-BBHLgo
I'm not recommending them, I know nothing about them, just passing it along for you to check out yourself

Most manufactures no longer use magnets in engines because there just isn't a lot of wear in modern engines. What does wear will be caught in the filter, which is more effective than a magnet since it captures non-magnetic (aluminum) elements as well, not that there should be much of that.

Transmissions have magnets and heavy duty filters and/or removable pans to clean because you have infinitely more wearable components. The bands (which are essentially brake pads) create most of the nasty stuff and are the primary discolorant of transmission fluid. Clutches in the valve body and gears have some wear, but again, in modern transmissions the shavings are pretty minimal. These are the only steel components. All static components in a transmission are aluminum. They have been for decades. In some transmissions even the pan is aluminum.

So in the end, if you add a magnetic oil plug, I'd be surprised if you ever found anything on it.

Won't hurt to. I had a bunch of hard drives that i wasn't using. Of course they had very strong (nickel plated) neodymium magnets. I slap one or two on the oil filter and call it a day. The transmission and diff fluid drain plugs already have magnets of their own.