You could also fabricate a wooden shelf / platform that's level with the rear load deck. Unless the rear floor space is handy for you.

Just fold it down? It converts into a perfect flat platform, why even bother with the removal? The seats also take big part in sound dampening.

I have removed my 2001 V70 rear seats for repairs. As I remember, they are very light. Not much weight to be saved, but if you want more room, even folded they take up considerable storage space. With no passengers besides my wife, my seats is always folded down. The same way I used my 1975 and 1983...