The mentality of Singaporeans and Nzers are as different as apples and oranges. Singapore parents fret when there are no tests, exams, assessments and tons of homework for their children. Private tuition is a way of life in Singapore while sports, social interaction and other cultural activities are viewed as essential by NZers.
Primary schools in NZ are geared towards social interaction and childhood development whilst providing the basic curriculum of physical education(sports/games), reading, writing, arithmetic and science. No pressure learning or overloaded curriculum.
If Singapore has removed Sec School banding to remove elitism , then it makes little sense for requiring PSLE to decide how to post students to the Sec Schools.
In NZ, the major exams start at Year 11 (NCEA 1) equivalent to your Sec 4 or GCE 'O' levels.
At Year 13 (NCEA 3 exam) if one passes and attains the minimum standards, one qualifies for entry into any university. Of course competition for the more popular professional faculties like Medicine, engineering, law etc exists.
I reckon Singapore parents won't like the NZ Education system because inwardly or subconsciously they don't want their elite children to be mixed with the lesser children of the Ah Bengs and Ah Lians.