Basically there are currently 3 airlines flying direct from Singapore to Ipoh and I have tried all 3
Malindo Air ( This has since been discontinued )
10:00 am departure, reach Ipoh 11:25 am
7:20 am departure, reach Ipoh 8:40 am
3:20 pm departure, reach Ipoh 4:40 pm
9:40 am departure, reach Ipoh 11:20 am
2:30 pm departure, reach Ipoh 4:10 pm
My favourite is Malindo Air because the planes are new with a touch screen entertainment system , and also the ambience is better than the other 2 air lines. (Malindo has since been discontinued )
Well it depends on what you like to see, if you have relatively more time, then the train option is not bad as well, quite an experience to take the train looking at the country side. But then the timing of the train and the recent spike of prices of the express train from KLIA to KL Sentral is not very encouraging.
For me I think it is still better to fly direct as within 4.5 hours maximum, you will reach door to door from your house in Singapore to anywhere in Ipoh, inclusive of flight waiting time.
Once you land in Ipoh, you will immediately feel the tranquility and you can see that you are surrounded by hills. The airport checkout is a breeze cause of the small airport size