This was kind of interesting. Forgive if this has already been examined :
http://www.youngcomposers.com/articles/Verdi-vs.-Wagner (http://www.youngcomposers.com/articles/Verdi-vs.-Wagner)
I thought it was pretty strange to deem Verdi's operas as lacking the complexity/etc. of Wagner's until Aida. The Great Trio of Trovatore, Traviata and Rigolletto are comparable from most perspectives to most of what Wagner wrote, in my humble opinion.