My wife's boss owns a Lancair IV-P
His has a 350 HP piston engine. I'd love to be able to afford a plane that could pass his. They hope it'll cruise at 340 knots (391 MPH, wow!). He's a doctor with a very successful eye surgery practice. I really don't know how satisfied he is with the plane. Apparently, he's had a lot of maintenance issues. The turbine engine version should be more reliable.
Of those other "dream machines", the only one that interests me is the personal helicopter. To date, I don't think it has flown. Until it flies, it's just another dream that may or may not work. We'll see.