I think that because of the popularity that Metallica got in the beginning they were able to overshadow the music that Dave was creating. He had to be different than Metallica or be known as a copycat artist and that difference is what held him back during the metal movement in the 90's.
Of course add that all on top of the negative press Dave would get about being a difficult person caused him to take a back seat to Metallica, but I really love Megadeth's albums and remember growing up with them and love revisiting them at this time in my life. I recently purchased "Peace Sells, But Who's Buying" earlier this year and it took me right back to my teenage years hanging out in my friend Shane's room smokin' weed and headbangin'.
Add when you also include that Megadeth has some of the most bad ass album covers ever, and Vic is one of the best mascots next to Eddie of Iron Maiden. Here are some examples.


