I have a MK10 which I used in the Tornado and also in the Extra 300L. They are much lighter than the MK4, so better for aeros or if you have to eject.
I also have a converter to change the single NATO plug to the twin civilian plugs.
If you want to make me an offer then I am all ears, but it would have to be more than Mart are charging, as its to the latest mod state and come with mask and adaptor.
Regards
C210H