Howdy!
Scott here....I've owned N9240M - 1966 M20E - for exactly one year as of last week. I've put about 125 hours on her this year and absolutely loving it. 40M has not been upgraded far from stock (yet), except a cowl enclosure and the 3-blade prop (upgrade or downgrade is debatable ). I plan for 150kts to make the math easier but I usually end up at about 148kts true.
I'm planning extensive mods over the next few years, assuming I don't outgrow the plane first, so if any of you have pics of restoration and upgrades, please post them! I have a 201 cowl in the attic and will begin collecting parts to install it next year. Other upgrades planned are removable/folding reat seats, new windows, new interior leather and plastics, 201 style instrument panel, 201 windshield, and the usual gamut of of fairings and gap seals. By the time I get all that done, maybe I can afford to do the IO-390 STC too....so barring unforeseen circumstances, I'll hopefully have the fastest E out there one of these days.