KK hands down if you are not not from the north or north Klang descendant. The place is smaller and isn't planned as a full fledge standalone city from the beginning. But it is well connected and located closely to fully matured urban area such as USJ, Subang, Puchong & PJ. 30min advantage to KLIA and Putrajaya. Well connected to these places from multiple express ways, KESAS>LDP/NPE, LKSA>Federal, Elite>NKVE/MAX... vs a place that only rely on one way and one exit. And with this connectivity, you are 30min to the best hospitals in Subang and PJ. Nothing beats that for an urban retirement home.