from your description, i think you prefer LH to Vic just that Vic is closer and they have better teaching resources
if i were you, i would consider:-
-) how much time it will take for your child to travel to school? if it is approximately or over an hour, i don't suggest you to, unless you are willing to move closer to the school and go to kowloon side as you aim at CKY
-) are you willing to put in a lot of efforts to train up your child for dss? i think LH has good offers including CKY not only because of their teacher style and reputation, but parents put in A LOT OF resources, time and efforts to train up their child, if you are willing to, go for LH since you have specific targets like CKY
-) vic has their own VSA but LH doesn't, is that one of your considering factors? do you like VSA?
1) travelling is very exhausting for kids and may affect their learning and resting time
2) even now you are at pm, you can make request to change to am but it may take some time
3) if you like IB, vic is the only school in hk that offers IB from kindy
4) even though its not 100% guarantee that you can get to vsa, it is better than 0%...