Downlights - 4 incher or 6 incher with or without glass
Bulb - energy saving or 'coiled' looking ones or LED

Apart from those, gotta take into consideration your ceiling height.
Say standard 2800mm, you may go for 1pc downlight for every 1 meter (4 incher).

Just a guide, there's no rule. It's a matter of preference, mixing and matching.

Avalon, GDO and TSEN for good lights. We personally recommend them.

Of course, there are few Avalons. We have yet to visit the largest one you see at the turning at Puchong.

Can't compare to Top Ten. They are no doubt not just affordable, but cheap.

However, Avalon and TSEN have much more outstanding lights. Seriously, you can't compare the level and products in which each pushes.

There are heaps of nice ceiling mounted-type of lighting nowadays. Just a matter of searching.

Puchong, Sunway Damansara, SS2, Sungei Besi. start your search there.