Mustang, on the question about a CD or DVD player, DVD players also play CDs well since their laser can also operate at the frequency that's optimal for playing CDs. So no, there's no benefit in a "dedicated" CD player.
As to advances in CD players, the technology for playing CDs has been mature for many years and the information on the disc has been read and output without audible flaws. If your 10 year old player is still in good operating condition, it'll still do this and there'd be no sound quality reason to change.
