Get the LeMond, it's truelly a great handling bike.
On the topic of Scandium, I see that the myth that Scandium is stronger is thrown around quite liberally. Unfortunately Scandoium is not stronger than other aluminium alloys.
Scandium's advantage lies in the elements ability to prevent recrystallisation of the grain structure after welding. Heat cuases the grain size of aluminium to increase ( a bad thing). Scandium helps to control this. Smaller grains = smaller grain boundries, which helps prevent cracking of the material at the weld joint.
In essence al the SAcandium does is improve the fatigue life of the alloy, especially at the weld joint.
PSS: Buy the Lemond