Except for an SR-71, there is almost no greater aviation experience than being at altitude in a U-2… (Spaceflight doesn’t count for this).
At 70 000 feet, your blood will boil if unpressurised, and the outer air temprature is -61°C. Good thing there are space-suits to wear!
James May of Top Gear fame, took a flight in 2009 for a BBC TV special to commemorate Apollo 11. First video is the feature itself, second video is of some additional footage.
Note that the indicated airspeed at 70 000 feet is only 104 knots! (still doing 0.7 Mach, though!). I wonder what his groundspeed was? At this altitude, there is very little difference between stall speed and maximum speed, the so-called “coffin corner”.