Very few new razors or used ones that are well maintained will absolutely require a 1K stone; even to set the bevel. From a physics veiw point, ceteris paribus (all things being equal), the 4K can set a bevel just like a 1K; only it will take four times as many strokes with the same pressure to accomplish that task.
The recent 4k/8k challenge and my own anecdotal experience confirms that this Norton combo with leather stropping is sufficient to maintain a very good edge. I optionally like to use CrO on balsa after the 8k and before the leather stropping. Enjoy.