“It’s the very naive producer who works only on optimum systems.” -Brian Eno
It’s unlikely whoever is buying your records has anything better than an average hi-fi, boombox, car stereo, or ipod. I’d bet they don’t have studio monitors.
Recording & mixing solely on studio monitors is foolish. All that low end in the guitar? It’s useless in the small speakers. It’s just taking up frequencies the bass or drums or organs or tenor instruments can occupy. You have to be ruthless in cutting away useless frequencies so the record is loud & jumps out of all speakers. Make the record sound outstanding on little crap speakers since that’s where most people will hear it. I’ve found when I do this it still sounds great on the fancy speakers.
Love this. It’s not about the gear. In fact, gear can distract you from the essence of what you’re working on. Strip what you’re doing down to its bare essentials and evaluate that. If that comes off great, then it will work as it gets louder, starts to grow, or whatever. (And web designers can definitely apply the same idea to bandwidth speed, screen size, etc.)