Quality Grades for Embryos

Grade 1, 4 cell. I didn't know what to make out of it when they told me about it. They said it was beautiful and highest quality but I guess like everyone else I needed more proof. Haha. And to better understand the grading for the embryos:

Image Source: http://fertilitycenter-uconn.org/how-do-we-choose-embryos-for-transfer/

Where classification is done through:

Grade 1: Fully expanded, very thin zona, and distinct inner cell mass and trophectoderm 
Grade 2: Fully expanded, very thin zona and distinct inner cell mass. Clear or disproportionate areas in trophectopderm 
Grade 3: A single cavity occupying most of the volume of the embryo, thinning zona and distinct inner cell mass and trophectoderm. (Early Blastocyst) 
Grade 4: Hatched blastocyst. 
Grade 5: Expanded blastocoel, poor or no inner cell mass. Poor trophectoderm. 
Grade 6: Morula.