Will still prefer 128GB onboard memory due to faster access and less hassle. 64gb $299 cannot use the $40 off $300 vouchers if you have CitiBank/StanChart cards.
$349 - $40 = $309, -$15 = $294
$299 - $20 = $279, -$15 = $264
Edit: 64GB also free cooler?

So 64GB = White Cooler, 128GB = Black Cooler?
https://shopee.sg/-1-Year-Local-Off...obal-Version(6GB-64GB)-i.178877065.5448939542
POCO X3 NFC Global Version(6GB+64GB)
With a FREE Black Shark FunCooler for any purchase in Sep. 9
Don't forget to put it in the shopping cart together!
https://shopee.sg/-1-Year-Local-Off...bal-Version(6GB-128GB)-i.178877065.4648934768
POCO X3 NFC Global Version(6GB+128GB)
With a FREE Black Shark FunCooler Pro for any purchase in Sep. 9
Don't forget to put it in the shopping cart together!
Dunno how it works, need to manually add cooler? Even got a "test" page for 128gb free gift.
[Test] Xiaomi POCO X3 NFC Global Version(6GB+128GB)
https://shopee.sg/-Test-Xiaomi-POCO-X3-NFC-Global-Version(6GB-128GB)-i.178877065.5651491689