The go to whetstone for beginners, you will forever need a #1000 grit stone. No matter how many other grits you add to your progression every knife you sharpen will come into contact with a #1000 grit. Still capable of doing minor repair work with heavy pressure, lighten up on your hand pressure and you can achieve decent polishing as well.
The traditional line from Naniwa is on the softer side and tends to be a little more forgiving if you make a mistake than the Professional line. The traditional line easily develops a “slurry" which is great, but wears down quickly and is more susceptible to developing ruts.
All of the whetstones sold at the shop are Waterstones, do not put oil on any of them, you will ruin your stone. Holding the knife at a consistent angle while sharpening is one of, if not, the most important thing to consider when sharpening; thus, maintaining a flat stone is of equal importance. Pick up a truing stone to maintain a flat stone in order to achieve the best results.
If your stones are super worn out and completely concave using a truing stone will take hours to flatten them. Consider purchasing a Kind flattening stone to get the job done quicker.