Machine-/hand lapping:
It take less material then there are less risk to weakening the chrome/nickel layer by mechanical stresses.
you can feel there are cylindrical, bellmouth or tapered and make true bore while you are lapping since there are not springness in lapping tool. You can adjust more or less tapered shape in sleeve depent on which sleeve are made for Mehanite/steel- or ABC/ABN engine.

Hand honed: Can make true bore, there are the risk to distorting the sleeve since the hone stone can tilt in wrong way and make unwanted shape such as bellmouth or tapered (i experienced when i honed the sleeve in Sunnen honing machine, i got bellmouth shaped sleeve. Maked 2-3 new sleeves without luck. Learned out the machine was worned or bad maintenance.) The stone need maintenance with special restoring tool before honing can start. Difficult to feel there are cylindrical, bellmouth or tapered while you are honing since there are springness and tilting stones in honing tool.

Grinding machine can you see in this link : http://www.modelenginenews.org/pb/index.html

Both honing and lap tool can you adjust diameter each time the bore diameter are increased + stone/lap tool are worned out.

Training in grinding technique make master either one are using grinding-, honing and lapping machine.

To make lapping/honing short and economical as possible will be done if surface are smooth and true as possibe to examlpe the bore are reamed then tool marks by lathe tool are removed before honing/lapping can start. The boring tool can spring and make chattering marks in sleeve if incorrect use or the tool are not sharp enough. It is important to save so much time to use grinding tools effective and less waste at loss of grinding material. The trained machine operator will hone/lap in some minutes for each sleeve.

The other are the roughness as we can see in these photos in early post there both pistons from Thunder Tiger 07 GP and OS 21 SE-M has difference surface, in smaller model engines are rougness more important to get short running-in and less loss of material of piston/sleeve. The bigger engines can tolerate more roughness without greater loss of compression.

Surface roughness is defined by the minute variations in height of the surface of a given material or workpiece. The individual variances of the peaks and valleys are averaged (Ra reading), or quantified by the largest difference from peak-to-valley (Rz).