*EDIT - I moved it to the correct forum for you.
Hi there.. you will get a better response in the Giant Scale 3D forum located here.
http://www.rcuniverse.com/forum/forumid_110/tt.htm
The 2 servos of choice here will be the JR 8711 or the Hitec 7995,
Both are more than powerful enough for this plane. Their site seems to be down, so I cant tell if it used 2 servos per wing or one. If it uses 2 per wing than you can use 2 lesser torque servos and add them together to get the total amount of torque.
As a personal rule of thumb I always use the best servos I can afford... these servos can be rebuilt and transfered to even larger planes. For example you will see many using 3 of the mentioned servos per wing on a 41%er.
Hitec has Titanium gears and is programable.
JR centers a bit better and is slightly smoother.
Both are great servos.