Honda Shadow Oil Plug Bolts - Should They Be Magnetic?
Magnetic Oil Plug Bolts: You don't "need" need them, but I think they're great! They won't make your bike run faster, but on the off chance that some metal shavings happen get in there, it'll grab them to allow your oil to keep pumping freely through your system. On Honda Shadows, the transmission, clutch, valve train, pistons, etc. all use the same oil, so whatever you can do to keep the oil clean and running smoothly is a win.
Bottom line: A magnetic oil plug is a great idea. You can also be super cheap and get some rare earth magnets from Home Depot and stick them on the back of your oil filter. That'll essentially accomplish the same thing.
*I recommend you change your oil every 1500 - 2,000 miles for best results!*