Good question. It used the same name as other aircraft built by the same manufacturer(clue 23). The fuselage, with some minor changes, was the same as another experimental one off plane(clue 11).
AFAIK, it was unique other than those two things. Now, time for more clues.
Looking for an aircraft:
1) This plane was built by a well known manufacturer
2) This plane was designed to use tech that was new at the time.
3) This plane featured a single engine and crew of 2
4) The tech used in this plane was also used on planes manufactured by allies and adversaries, some of which became legendary
5) Several of the planes referred to in clue 4 had service lives of over 20 years
6) Only one of the subject aircraft was built
7) The plane was cancelled due to two things the government couldn't overlook
8) The engine was not manufactured by the country building the plane
9) The single engine design did not give the performance or survivability desired.
10) While the plane was destroyed during it's third year of testing, the pilot was unhurt due to bailing out
11) The plane in question shared a fuselage with another aircraft that was also destroyed during testing
12) While the plane was completed in June, it was not flown until November due to changes, reworks and technical issues that had to be resolved
13) The time taken to go from first test flight to reaching it's top speed and performance capabilities was just over a month
14) From first flight to destruction of the aircraft was 38 months
15) The plane is question had a top speed comparable to many of its contemporaries of the day
16) Since the plane was not produced, there was never any weaponry or hard points installed
17) The plane in question had a ceiling of almost 61,000 feet and a maximum range of almost 2400 miles
18) One of the "legendary" aircraft had side by side seating for the crew while the aircraft in question had tandem seating
19) The "legendary" aircraft was originally designed to have the same mission as the aircraft in question but, due to operational requirements and results of testing, it's mission profile was changed
20) The "legendary" aircraft, other than the seating arrangement, actually looked very similar to the plane in question
21) The manufacturer of the aircraft in question has been around for close to 100 years
22) Unlike planes used in earlier wars, the plane in question used a feature developed by an ally that prevented compression issues in a dive
23) This plane's given name was used again on another aircraft that was not only successful but has seen combat operations
24) Like the "legendary" aircraft referred to in clue 18, the aircraft in question was designed to be used by both the Air Force and Navy of the developing country. Neither plane ended up meeting that goal
25) The feature that tied all of the "legendary" aircraft to the aircraft in question was actually experimented with by an adversary earlier in the century.
26) The feature that was referred to in the previous clue was only able to be used on the ground when it was first tried. The "legendary" and subject aircraft were able to use the feature in flight
27) One of the "legendary" aircraft became famous for an operation that it was used to accomplish while another was made famous not just for what it did operationally but also by what the military did to "show it off"
28) All of the other aircraft built(AFAIK anyway) with the the new tech, regardless of manufacturer, had at least two engines
29) Speaking of engines, one of the issues with the subject plane's engine was that it came from another continent, something that made shipping and receiving problematic in the event of hostilities.
30) Even though the subject aircraft was single engined, unlike the others from other manufacturers, it was supersonic capable like all of the other's with it's new tech
31) This new tech, used on the subject aircraft as well as the several "legendary" aircraft, was even planned to be used on the initial design for a Boeing built rival to the Concord that never got past the mock-up stage. That transport was later revised to a delta design with separate horizontal stabilizers
32) Some of the "legendary" aircraft were named after animals. Others were named after various types of weather.
Good Luck