Man, it's funny that so many people have Youthanasia in their top 3's. Youthanasia was universally panned, and just completely, all-around shit on since it's release...and now it seems like, in the minds of the fans, it's one of their most well regarded albums.
I like Youthanasia a lot, but it has one major, major problem. Every song is at the exact same tempo. Apparently this was Max Norman's recipe for Megadeth acheiving Metallica's level of mainstream success: Put every song, whether it's a ballad or an uptempo song, at a tempo radio stations will play, and hope one of them sticks.
This horrific production formula really killed the album. The songs are good, and a few of them I really, really dig, but they're not the songs they were meant to be. Dave has stated on multiple occasions that he made huge compromises while recording this record....and it sort of shows.
For the best of Friedman/Menza era 'Deth, give me R.I.P. or Countdown to Extinction over Youthanasia any day.