Speaking to my importer, 1.23m would be a special order as the standard lengths offered are 0.5m / 1.0m / 1.5m. The thinking was also that a length of less than about 0.75m could act as an AERIAL and longer was better, but the Silverstar Mk2 (red & black) changes over the Mk1 (white) includes a screen to reduce / prevent RF interference and therefore addresses the problem so that even the 0.5m works well.
This is not my opinion, but what I am told.