I do not know how legit this site it, but it compares Wounded Warrior Project to other charities:
http://www.charitynavigator.org/index.cfm?bay=search.summary&orgid=12842
Charity Navigator gives Wounded Warrior Project a score of 84.52%.
If you search Charity Navigator for “veterans” and sort by score, Wounded Warrior Project is in the middle.
For comparison, Charity Navigator give the best scores to these
99.2% -— Special Operations Warrior Foundation
http://www.charitynavigator.org/index.cfm?bay=search.summary&orgid=7584
98.98% -— Navy SEAL Foundation
http://www.charitynavigator.org/index.cfm?bay=search.summary&orgid=13076
98.83% -— Southeastern Guide Dogs
http://www.charitynavigator.org/index.cfm?bay=search.summary&orgid=8896
97.71 -— Injured Marine Semper Fi Fund
http://www.charitynavigator.org/index.cfm?bay=search.summary&orgid=11708