Finally got a chance to play a game with 15s using centimeters instead of inches. We used a standard 4' x 6' table and about 1500 points. All in all we felt that the game played better in centimeters with possibly two exceptions.
1. The deployment zone was too small if measured in centimeters which was easily fixed.
2. Fire zones and lethal zones seemed to small. I had mounted my foot troops on pennies as a solid base. They are just a tab bit under 2cm in diameter which meant that foot troops would have to be base to base to have multiple hits from a Lethal Zone/1 blast. We didn't have a good fix for this other than reducing the rulebook measurements by dividing by .5 inches or doubling them for centimeters.
However, the game had a more tactical feel to it. We had considerably more maneuver room though the slowness of the tanks really showed up. A Sherman moving on 3cm an action made them look as they weren't moving at all. And moving 7cm using the Tracks/7 trait wasn't much of a help.
This meant that you had to truly consider you movement as it was move of a factor than if using inches. As a result, we felt that movement became a very important aspect of the game and as such factored in more of your "general ship" into the results. Sending units down flanks became more of a threat as they were more likely to be out of shooting range until they turned the corner and came down your line. If you didn't have a proper response it was very possible you would be caught in a crossfire and more likely to expose vehicles to flank or rear shots. We were not able to do this with out lots of scenery on the table when using inches, since tanks could pretty much shoot across the table easily taking out a flanking move before it could get started. The only way to avoid this is to play on a larger table when playing in inches which rarely is possible. Therefore when using inches movement wasn't quite a factor and game results seemed more of a factor of dice rolls.
I would encourage anyone playing with 15s to try both and see which they prefer.
For us, playing in inches makes for a fast and bloodier game (which is not to say is bad) while playing on the same size table using centimeters was more like a chess match.
Either way all our games were enjoyable.
By the way, the centimeters game came down to both of us being 1 model from breakpoint. I had two Shermans taking shots at a halftrack. The first missed, the second hit on the side armour but my opponent made his 6+ save (he did that several times in course of the game). Unfortunately, my infantry HQ was exposed to his two StuG IIIs and as you can guess it was game over.
