pretty soon every house will be made with pre made panels; i see it now on a lot of construction sites ( the smart ones) - qualtiy quality quality every time...
Re: panelized walls w/ electric built in factory; I suppose it needs splices or junctions to have longer wire runs to neighbor panels ongoing to brakers.
Do all panels still require craning in? I have a site behind a single family house that is somewhat surrounded by powerlines and limited to 115 inches on the side of the house and thought sips would be a solution, but it appears craning is still necessary.