Correct. As far as I can tell, Battleore Hex = BoW Hex > Memoir Hex BUT the difference between the latter is tiny. Of the order of a millimeter maybe. In fact I'm considering playing BoW on Memoir breakthrough map... but that's OT.
The hex sizes of most Commands & Colors games, including Battles of Westeros, are around 53-55mm. The terrain should be compatible. Samurai Battles and The Great War use slightly larger 60mm hexes. BattleLore second edition hexes are are 70mm.