Which telco actually has good coverage for balik kampung to the East Coast?

From my experience driving KL to Kota Bharu a few times a year, Celcom (now CelcomDigi) tends to have the strongest coverage on the East Coast and rural interior, especially around Gua Musang and the smaller towns. Maxis is decent in the main towns but can drop in the deep stretches. What I do is keep a dual-SIM phone with CelcomDigi as primary for the trip. Coverage really depends on your exact route, so ask relatives in your kampung which line has full bars at the house. Also check the coverage map on each telco's website for your specific area before committing to a plan. Networks keep upgrading, so this changes year to year.

I travel to Terengganu often and honestly the best test is to buy a cheap prepaid SIM of the telco your kampung folks recommend and try it before switching your main line. In my case CelcomDigi worked best in the rural parts, but a friend in a different town swears by Maxis. For the highway stretches with no signal, don't stress too much, download offline Google Maps and your Spotify playlist before you go. If you need to stay reachable for work, a second line as backup is worth it. Coverage is very location-specific, so real local feedback beats any general ranking.