3% is like house loan....the faster you pay at first, the lower the interest rate that you will be paying after annualized.
1% is like car loan, which if you are paying over >10years, 1% is cheaper.
Eg 50K for 15 years
If 3%, total interest paid will be >12K
If 1%, total interest will be 7500 only
On both occasion assuming you are paying according to the schedule.
For my case, I pay more during the first 4 years, so the interest rate is a whole lot lower, should I change to 1% now. Besides, my loan is just 21K, so can better settle asap without changing plan and going through all the hassles. Bear in mind, if you wanna go oversea after you sign the 1% agreement, you need to tell 3 months upfront.
I'm not here to discourage people to change to 1%, just IMO it doesn't worth the hassles, just me. Fact is, I even encourage my friends to change to 1% as their PTPTN loan amount are huge....

My loan is around RM40,000.00. Should I convert it to 1%? I was thinking to fast-fast pay finish also.
Jumlah Ujrah = Jumlah Pembiayaan Pokok x Kadar Ujrah (1%) x tempoh bayaran balik (tahun)
I got this formula from the PTPTN pdf. So what would be the interest be after conversion? Need to pay ikut tahun?