You saved nothing. I travels every day for work from Kuala Kangsar toll to Simpang Pulai toll (RM4.35). On the way back from work I sometime exit Ipoh Selatan and enter back at Ipoh Utara, no difference in toll rate (still RM4.35).

Route 1:
Enter Simpang Pulai Toll -> Exit Kuala Kangsar Toll = RM4.35

Route 2:
Enter Simpang Pulai Toll -> Exit Ipoh Selatan Toll = RM1.48
Enter Ipoh Utara Toll -> Exit Kuala Kangsar Toll = RM2.87
RM1.48 + RM2.87 = RM4.35 (Same!)

If you have no plan to stop at Ipoh, better continue heading north using highway.