Transferring from RC to IS/ESF in HK Island

My son is now in Year 3 of RC (Renaissance College in Ma On Shan). However, since my family got to move to HK Island, I am now looking for IS in HK Island for him.

We must move to Island side by July 08. I'm now considering both enroling him to the new school immediately (Grade 3, or Grade 2 in some IS) and for next academic year (Grade 4, or Grade 3 in some IS).

Am thinking of ESF (not sure which one should I apply for), Canadian and German Swiss. Know that CIS and HKIS are good but their tuition fees are too high for us.

Apart from the above, any parents have suggestions for me

Any tips for me to find the place asap ?

Thanks
Ruby