Over rated guys for me are guys like polyphia, and modern stuff of that genre, to similar sounding. Their albums are almost like 1 hour long songs rather than a varied journey.

Under-rated guys for me are Tramaine, Marco Sfogli and Al Jospeh. All of these put music first. In particular, Tramaine is known for shredding at stupid speeds accurately, yet sparingly does it on his album 'Heavy balance'. Which I thought was a great sign of how an artist should approach guitar music