Ah yee olden G2X! Such a shame the US version was never updated to ICS. Many devs tried their best to upgrade it beyond GB, with mixed results. Thankfully those days are long past. With phones such as Moto G being able to please the vast majority, and OnePlus for the power users, things are looking bright indeed.
4 cores is quite noticeable in performance, though I'm really looking forward to big.LITTLE. High speed, user-facing snappiness and lower powered background processing is going to be very nice.