Hi Nick,
Do you have other reference materials/books where you can look up MT inspection and the different variations of MT inspection?(some methods use portable equipment to use in the field, others use stationary equipment that stays in the lab)
Once you understand the principles involved with MT inspection and how it works, I think you can answer your own question. Of course I could blurt out several advantages and disadvantages for you, but it will stick with you better if you can look it up and see it for yourself. If I know what books you have available at your disposal, Maybe I can help point you to the answers you are looking for.
Here is a link to get you started in case you don't have any NDT books handy.
https://www.nde-ed.org/GeneralResources/MethodSummary/MethodSummary.htm