All things being equal (hypothetical) which do you prefer, XLR or RCA?

More great responses! I do love the locking grip that XLR offers. What I have noticed though is that some manufacturers charge the same for XLR or RCA. While others charge almost significantly more for XLR (Transparent Cable-not a knock I do love their cables).

This is awesome, thank you all you've certainly ticked the box for "having some fun" on this one :)!

Same cable same manufacturer (Kondo KSL), i like the balanced connection for a more relaxed with more body presentation as having the benefit of the extra gain. But i also like the slightly better mids and energy on top and the slightly better pace and attack with single ended connection. 
Dynamics i would call equal.
Both my pre and power amp are true balanced designs.

G

XLR

Simply stated differential balanced means no signals are on the same boards, which 100% eliminates cross talk. Anything less, should NOT be considered Hi-End

XLR, provided that the components to which the connection is made are truly balanced.