I wouldn’t recommend splitters. They may introduce more uncertainty into the equation.
I want to reinforce the idea of long comparisons. A few quick swaps will tell you if there are any huge tonal differences or detail differences. But long… I recommend at least a week listening to music (not the system)… two is better auditions… then switch. This will allow you to understand the sound much more deeply and make the comparison. Typically, taking a lessor component out is where the real moment of understanding comes.