IndieFan
118
At 42mm... New Resonance or Optimum
Chances are that the new Resonance will be in 42mm... so you may have your wish to get an iconic model that FPJ created and tinkered with himself.
If 42mm is your must have, then it leaves two options only in my view... new Resonance or Optimum. The Sonnerie is also 42mm if your budget stretches this far
There are other iconic FPJ's like the original brass movement Tourbillons or Resonances, but they are 38mm...
As far as icons, its usually the Tourbillon, Resonance, Optimum and Sonnerie (this last one is an icon, but not the easiest to obtain), and not necessarily in that order!