I'm curious about the Naniwa economical series, as they are smaller and I like to hand-hold the stones, rather than use them on a bench. Also because I like the Suehiro 1k/3k combo stone prior to moving to natural stones.

The Naniwa economical line comes in 120, 1000, and 3000. Any thoughts on the viability of using the 120 stone as a lapping stone for the 1000 and 3000? I'm supposing I could keep the 120 refreshed by lapping it on 80x wet/dry sandpaper on glass and that the stone would be smoothed by the 1000 prior to moving to lap the 3000.