Phyre2 vs ITasser, completely different models generated
I'm less familiar with Phyre, but I-TASSER is a really sophisticated system that takes the results of a search using multiple threaders and plugs them into an ab initio simulation which tries to minimize the energy of the models by sampling many possible 3D conformations, which I don't think Phyre does.

https://en.wikipedia.org/wiki/I-TASSER#/media/File:I-TASSER-pipeline.jpg

Compare with a similar workflow schematic for Phyre:

http://www.nature.com/nprot/journal/v10/n6/images/nprot.2015.053-F1.jpg
http://www.nature.com/nprot/journal/v10/n6/fig_tab/nprot.2015.053_F2.html

Structure prediction still has a long way to go, and you'll always get better results if there are close homologues available in the PDB, but given the consistent high performance of I-TASSER in CASP I would treat those results as more significant. That said, it can't hurt to consider multiple answers.

Edit: included blmoore's link to second half of Phyre protocol schematic