It's explicitly stated that support both interband and intraband by Xiaomi.

Mi5 support Digi 4G+ but it won't be shown as 4G+ as it only utilized 20MHz bandwidth.

Because 20MHz of contiguous bandwidth is achievable even without CA on few primary LTE bands so some device only recognize Digi network as LTE Cat4 network and hence 4G+ is not displayed. LTE-A or also known as 4G+ is aimed to achieve Cat6 speed. If you have a 3X CA device, it's better because you could connect to 2X CA network but when you only have 2X CA phone you could only use 2X CA and not 3X CA. 3X CA is not used in Malaysia so you don't really gain any benefit from it. Our neighbor country Singapore's SingTel had 3X CA and South Korea's SK Telecom, Korea Telecom and LG U+ had 3X CA. Hell, even SK Telecom had plan to roll out 4X CA.

Redmi Note 4 only support intraband CA and Digi is using interband CA.

Let me give an simple example
Interband 20+20MHz from Band 3 and 7 each 20MHz
Intraband 20+20MHz but both must be from the same band either Band 3 or 7
Xiaomi doesn't enable interband CA to differentiate Redmi line from the flagship line.

Redmi Note 4 doesn't support Digi 4G+ as it's Digi are using Interband CA and Redmi Note 4 is Intraband CA. Interband CA phones can utilize both type of CA and Intraband only work on Intraband CA.

If you plug China Mobile sim card into Redmi Note 4, it will show up as 4G+ network because China Mobile had Intraband CA at Band 41 + Band 41.

Yeah, you're definitely right.
BTW, I'm not an expert in this just someone who spent considerable huge amount of time into learning all these stuff.

22.5Mbps maybe

Seems like the only telco without indoor booster is Yes. I've been to Queensbay Mall and no signal all the way in LG floor. Ground floor had terrible signal strength and signal strength starts to improve when I go higher floors.

Broadband number unable to perform MNP

Webe had 2G roaming agreement with Celcom also??

The quota is so much that it's unlimited for majority of the users

The quota is so much that it's difficult to fully utilize without tethering to computer

Blaming telco for when you're lazy to read up the TnC are similar to blaming Havard University for setting up extremely high barrier when you didn't perform well enough to enter

I can't deny the second statement but some people always pretend to have victim complex when they are just too lazy to read

It serves them right for not taking time to read TnC provided that that particular product or service is not falsely advertised.

If you want to talk about unlimited, U Mobile isn't true unlimited either. It's only good enough to qualify as unlimited quota.

What about SNR value? You must have very poor or even negative SNR to achieve such bad speed on LTE.

Usable only on weekend though

Unlimited with FUP

Just for calls only