I like their comparison:
What’s in the SIM Pack?
The new U Mobile SIM Pack costs RM8.50 and inside it comes with RM5 credit preloaded. Upon activation, you’ll get 200MB of internet and 150 minutes of free calls within U Mobile. By default, the SIM pack comes with 10 days validity. In term of rates, it will cost 10sen/minute (30 seconds block) for voice calls and 8 sen per SMS to all networks. On top of that, U Mobile is offering 450 minutes of free calls to your friends and family who are on U Mobile’s network each month. This is given as a daily 15 minute free call quota during its active period.