You might think that older retroconsole ardware would be extremely unreliable, but if you buy a 20 year-old Super Nintendo today, it will likely have quadruple the lifespan of the original Xbox 360. Why this ? That's a conservative estimate, too ! Nintendo built their old consoles in such a way that they would often survive being inside of vehicles during car crashes. The original model of the Game Boy can survive an entire winter buried under snow, and one man recovered his after the external shell had been warped and charred, and it still functioned.
There are so many under-appreciated classics that will never be ported to modern systems, and there are whole genres that have all but died in the current AAA landscape. While old games have their share of flaws, you'll also find some of the best games ever made within their ranks. If you like Japanese style RPGs, platformers, and turn-based strategy games, you'll never make a better investment than an SNES, a Genesis, or a Playstation console.