The rings are lapped perfectly cylindrical and smooth in a tool steel tube at the time of manufacture. They virtually do not require any seating. What little "break in" takes place is kept to an absolute minimum by ensuring the rings are smooth and the walls have a finished plateau surface devoid of any raised wear points. The top ring is a steel nitrided ring and virtually requires no "seating". Secondary compression/oil control is cast iron and these will seat easily with no honing at all. Indeed the Subaru rings are so thin that honing the cylinder is likely to overheat the rings and cause them to lose their spring tension resulting in WORSE compression. Also the wear materials and impregnated honing grit will tear up your bearings and shorten engine life as they mix with the oil and end up through the whole engine.
Show me a mirror finish in a used Subaru bore and I'll show you a block that needs to be bored oversized due to excessive wear.
There are NO cases where a flex hone is a suitable answer. If the bores have so much wear that all the cross hatching (which are the valley's of the plateau finish) is gone, the bore is SHOT and no amount of honing will bring it back. It would require a rebore to the next piston oversize, and the last step in that process is a proper diamond finish plateau hone.
I can produce references from the 80's that were already stating not to hone cylinders on a rebuild unless absolutely necessary if you want to achieve quickest seating and highest ultimate compression. Piston ring manufacturing, and engine manufacturing tolerances eliminated the need for honing on rebuilds back in the 1980's. Things have only got better since then.
The reality is - if the bore isn't good enough to run - you need to bore it out to the next piston size.
And more important than the cylinders BY FAR, is the line hone. After 100k the line hone takes on all the shape and appeal of an elderly bag lady. With the #2/3/4 main's having sometimes three times the allowable oil clearance.
And the best reason of all - I build Subaru engines FOR A LIVING. I do this every day and we build everything from stock to engines making well over 600 crank horsepower. I haven't honed a cylinder wall in 15 years and not a single engine uses oil or has failed to properly seat the rings. And they seat FAST. It has been (wisely) said that on the first revolution of the engine the rings are wearing in - on the second they are wearing out. I will typically do a 100 mile break-in and then we go full-throttle. My engines always exhibit perfect, uniform compression, and the oil changes show no wear materials. The first oil change at 500 miles ALWAYS shows ZERO oil consumption.
Oh yeah - and it isn't opinion. It's FACT. Once you have done this as many times as I have - it's not an opinion anymore. I speak from VAST experience.
GD