i suggest that it is alright for you to find apartment in both Fook Tin and Lo Wu districts. What you concern most is transportation and the management of the building. I think newly constructed estates suit you most.
estates nearly SZ metro will be very convenient for you even you living in some remote area. It takes only about 30 minutes from Lo Wu to "Windows of the World" terminal.
I dont recommend you to rent apartment in "Spring Wind" Road in Lo Wu district for there are too crowd and too noisy, though the shopping and transportation are convenient.
if you wife is willing to cook at home, you should consider to live near to supermarket or some local market.
Though the selling prices of SZ flats is rising drastically, the rent rate is stagnant.
good luck