To put the following into context, I teach at a UK university and have delivered courses at a Singapore partner university for many years.
In support of many of the above comments, you need have no concerns about the academic establishment in Singapore, at any level, from primary through to university. Education is top of Singapore's agenda and this is apparent everywhere. Teaching is in english throughout. Singapore's universities are world-class.
The living and working environments are excellent. Cost of living (apart from housing) is lower than UK. The transport system is also excellent.
Cost of accommodation is the only negative. Apartment rental costs are high - comparable to London. However, if you are appointed on expat terms the University will provide an apartment and the rent will be subsidised; all large companies that employ expat staff take account of accommodation costs. But you should make sure that you know what type of apartment is on offer and that it meets your family needs. 'Landed properties' form a very small part of Singapore's accommodation, the large majority are high-rise apartments.
Income tax is much lower than UK levels - you can check this out on the government's IRAS web page.