I have been in an 777 with 3-4-3 configuration. It's hell. So narrow, so long, so low. So little room everywhere. The restrooms are on the outside with a blank window (nice) but so small and so low - only smaller asian people fit in those small restrooms. The 777 is also quite loud and aged badly.
The A380 is very modern and no annoying noise. And so much space even in cattle class. Only US-fanboys would say the 777 is better than the A380.