Since when has the Montblanc Meisterstück 145 been produced, and why was the 144 discontinued in the classic variant but continued in special editions?

The 145 has been produced since 1998 and is essentially a variant of the Meisterstück (also marketed as Hommage à Chopin with CD); it is not to be understood as a direct successor of the 144, since there are no ballpoints and pencils in identical size to it. The 144 in the classic plug-on cap version was discontinued for reasons of product rationalisation, because the plug-on cap is regarded as a weak point and wears out over time; the replacement cap seal is not separately available and the service flat rate is comparatively high. In addition, the 144 had a screw thread metal on precious resin, which could lead to predetermined break points; on the 145, metal meets metal. In the Solitaire editions the 144 was retained, since these have a short screw thread between cap and reservoir and the range there continues to comprise ballpoint, pencil and rollerball.