And in Macau, you'd better concentrate on what this SAR is kept for*, namely: gambling.
I bought some nice garment and shoes there but never spotted any decent, large electronic store there.

*-Gambling, so beloved by Chinese people, is prohibited in Hong Kong and mainland. Interesting feature of today Macau is that, once under Portuguese rule, it was an obscure, dirty place with everybody speaking Chinese and hardly few Portuguese signpost - nowadays the Chinese governors equipped all the streets and places with new, prominet Portuguese signage. Maybe for the Chinese visitors to get the feel of a "foreign" country and thus to increase their desire to indulge in gambling?