Actually the best would be from a bodpod as you don’t get the unnecessary radiation.
The thing is both types of scans are really unnecessary as the knowledge you gain is mostly meaningless unless you just love knowing numbers. I imagine if you just had extremely little body awareness it could help but really it doesn’t matter.
If I can get an accurate bf and muscle mass then I can tailor my diet and exercise for what I need. I think people would be really shocked by what their actual bf % is compared to what they think it is. Even people that are “in shape”. It’s a motivator.