re: Voyager & Proteus both built by Scaled Composites
Four world records:
-- Voyager (Dec.27,1987) set the distance record for non-stop unrefueled flight.
-- Proteus (Oct.25 & 27, 2000) set three altitude records: peak altitude (62786 ft); sustained altitude in horizontal flight (61919 ft); peak altitude with 2205 lbs payload (55878 ft).
source: Janes ATWA
All speed records are held by rocket-propelled vehicles. I don't think there is any point trying it any other way.