Weighting the car during alignment

[4.8ISInCanada]

A little technical, but I know someone will have the answer to this.

What have you found is the best way to ballast the X5 to perform an alignment?

I have the specs so I know how much weight to place on each seat but am wondering if the best option is to a) weight it as specified with for example sandbags, or b) to weight it with myself and my wife actually in the seats, perhaps with a couple bags in the rear seat and one in the cargo area?

I know theoretically it might sound reasonable to use ourselves as ballast since that is how we drive alot of the time but as often it is only me and frankly, my opinion is equal weighting is more appropriate so I am really just trying to double-check my own view. For reference, my wife and I are quite a few lbs apart.

Also, if you can suggest something more efficient than sandbags (cleaner, cheaper, heavier), I'd love to hear it, if not sand is fine.