[QUOTE=One of the things I like about the sleep number bed is when it's taken apart (not a part

) it goes down to a much smaller item. Obviously. Sans the air it's a lot smaller, and the exterior walls can be replaced as they wear out without having to replace the part of the bed that lasts forever - the top. Portability is something I will always have in mind since I don't think we're done moving ridiculously far away. [/QUOTE]
We like our sleep number bed for this reason. I can easily move the bed around the room to clean or rearrange, since it is light, and it is easy to adjust firmness/softness for two different sleepers. We've had no problems with it.
Tempurpedic is supposed to be fantastic, but I've heard that they are heavy compared to regular mattressses. You might want to check on that if you think you'll be moving again.