links:
singtel
m1
starhub
Starhub's PowerValue 300 ($47.25) seems suited, free incoming all
day, free 500 SMS (more than enough), but you can only make
outgoing calls of up to 300 mins or 5 hours (by seconds).
If you need more time to talk to your suppliers and maybe family
members but paiseh to ask them to call you instead of you call
them, try Starhub PowerTalk II, 300 SMS, free incoming calls and
you get 680 minutes (>11hr) outgoing calls which is a lot. The
bad point? $92.40 per month.
And yes, additional $5 is applicable per month from the 4th month
onwards for International Roaming.
