So already picked up an issue with the Xiaomi Redmi Note 8.
It supports Telkoms Band 40 and carrier aggregation so will show 4G+
It does not support Band 1 + Band 3 carrier aggregation or 3Ca at all so that means normal LTE on Cellc,MTN and Vodacom.
At Work on Samsung S10 I get 80Mbps with 2 carrier aggregation. The Redmi Note 8 peaks at 30Mbps. At Work I get 105Mbps on MTN with 3 carrier aggregation B1+B3+B8 on the S10 while I get 25Mbps on the Redmi Note 8.
The Samsung LTE radio is far superior than the Redmi Note 8 which is a bit disappointing to be honest because phones priced at the same price range as this Xiaomi from Chinese brands like the Meizu does support multiple carrier aggregation including some Huawei devices.
The S10 is also generally fast than then Xiaomi but that I don't complain about as it is a R3049 phone vs a R15 000 so it's obviously going to be faster.
If you can look past some of these negatives and focus on the fact that after a full day of use like I use my S10 with the same apps, camera and data my S10 is dead by 15:00 while currently my Redmi Note 8 is still at 56% battery and I used the device a lot browsing, facebook ect.