Wow, after finished read most of the comments here, I've started to scare and doubt about whether I should get a iPhone or not?

I'm planing to sign the RM50 iData plan, and I think I won't heavy use in internet. Maybe just facebook and download some apps.

Because I saw a lot of complains about the data usage exceeded problems. And the iPhone will auto connect to Internet by using 3G even you're not online-ing?? Even connect to internet by using WiFi will get charge too??

So anyone can please give me some suggestions? I should get it or not? or I should just go and get a iPod Touch which does not has 3G connection >.<....

Thanks.