This is a topic that some people take way too seriously. The one factor you have no control over is the recording.Some recordings are inverted, and some aren't. So, regardless of how you set your gear up, you'll always be off on some of your music. The only practical solution, is some preamps and sources have a phase invert button on the remote. If you don't have one, I wouldn't worry about it. Unless you have a lot of listening experience and some very detailed gear, you're not likely to notice a difference. By all means experiment, but your time and money is better spent elsewhere.
Subwoofer Polirity
I have a Rogue Metis preamp and per Bill at Rogue I flip the polirity at my speakers. I've added a subwoofer and I'm running it the same inverted. Was wondering would it be ok to try running the sub with normal polirity and the main speakers inverted? Just to see it how it effected the sound of the sub. My mains inverted have less bass and better midrange and high end. Just wondering if I would get better bass if ran with normal polirity.