Well, tilt props is not a new invention.
The Curtis-Wright X-19 had four tilt props.
Focke had a tilt prop STOL.
I think prop lift is the way to go, but I prefer the method of Focke and Dornier (DO29). That is, extreme STOL first, to be followed with VTOL.
slowrotor
Dornier DO 29
http://www.!!!!!!!!!!!!!!/open.file?id=1179047&size=L