ID Core 20/40 new or old differences

[Pacemaker1000]

Not getting much support on this forum which is dissapointing!

Last try,
Narrowed down to 20 or 40 so questions,
Will the 20 sound better at lower volumes due to being driven harder or the same? In which case I'll buy the 40
Do effects units connected to aux in use the wide stereo mode and sound great?
If main use is using effects in from iPad interface is it worth paying extra for the new V2 units?
When/is the hiss problem fixed?

Come on mods or Blackstar support start answering customer questions!

Cash waiting!