There is a fix for the 4.8 plus 8. Mine was virtually impossible to fill in less than around 10-15 minutes, now perfect. It was done FOC as it’s possibly a safety issue. Two hours work so not widely publicised .
1969 4/4 1995 plus 8 1996 Plus 4 4seater 2002 Aero S1 2013 M3W 2014 Plus 8