Since choosing a PC case is completely a personal choice, go with the case that likes you the most.
I'd go with NZXT case, 2 reasons:
1. Besides supporting 120mm fans, it also supports 140mm fans. Bigger fans = more airflow with less noise (depends on fan used).
2. It has 1x top exhaust fan mount. Since hot air rises, the best exhaust fan is the top one. Without top exhaust, the hot air gets trapped inside the case.
Though, Thermaltake case does look fancier and i like fancy but the reality is that i prefer performance over eyecandy.