Power Redundancy vs. Hot Spare vs Disabled

Could someone please provide some clarity to the different power redundancy options in your 2x PSU servers (specifically R620s in our case)? Specifically:

From what it looks like, "redundancy" (in the iDRAC 7 power config) means a hot spare in the sense that the other PSU remains off until the first one fails (i.e. 1+0 I think). With"Hot Spare" and redundancy enabled, it looks like most of the load is on the primary PSU most of the time, but load begins balancing to the second as the load increases (but at idle the primary draws a lot more than second). 

With our situation, we'd like to configure so that both power supplies draw equally, all the time, and also provide for redundancy if one fails. What's the difference between hot spare enabled or disabled with redundancy turned off? It looks as though the load is always distributed evenly whether hot spare is enabled or disabled (with redundancy disabled)? Are there any gotchas to look out for?

Thanks a lot!