I don't know, you offer advice to other people and yet this is causing you to procrastinate lol
I have recently read many articles about portal builds and one guy, who virtually lives in his land rover defender travelling around the world, spent two years developing his axles from scratch.
Is it a portal conversion on a standard axles or a portal axle from say a unimog or merc etc that has been fitted?
Portal conversions using a transfer box on a standard axle are unreliable so purpose built axles are only worth considering IMO.
Advantages are too easy to list, disadvantages are more money thrown into a project to get it working than it could be worth.
However if I had the opportunity to do it, then I would definitely do it and #### the consequences, besides its summer soon so you can take a few months to get it right.
If you do get it, I baggsy the chequer plate kit lol