No need to go so far. depending on where is your location. HK$ is well traded here. So the diff between one money changer to another is very low.. No point spending toll & parking to MV to get the best. Anyway, Wawasan no longer the cheapest. You can find a better & more competitive rate from those Money changers beside, & infront of BB Plaza. Otherwise, just check few around your place & negotiate to the lowest. BTW, wawasan does not change small denomination.