TPLINK MR600 V2 : https://amzn.to/3mMyCpg
4G LTE Antenna : https://amzn.to/3e0ugGX
SMARTY Unlimited Data SIM UK : https://i.smarty.co.uk/CrQN3f

I compare 2 sims against each other using a dedicated 4G LTE Antenna, and the supplied rabbit ear antennas you get with the TPLink Archer MR600.

I did 4 speed tests, (and a 5th retest after the video. results below)

First Sim, Upload/Download
With rabbit ears,
7.73/9.06 (Network Type: 4G LTE)
With antenna,
8.59/1.81 (Network Type: 4G LTE)

Second Sim, Upload/Download
With rabbit ears
1.50/1.67 (Network Type: WCDMA)
With antenna
21.4/12.3 (Network Type: 4G+ LTE)

Second test using the second sim,
with rabbit ears
20.05/21.7 (Network Type: 4G+ LTE)

In both cases, with equal network types, I find the upload is better with the rabbit ears but downloads are only slightly worse.

Also, with the first sim, I have seen a network type of 4G+ LTE.
But generally, the second more expensive sim, in my case is better overall performance.

Also, sim quality most likely depends on where you are situated in relation to the 4g towers. Each supplier where I am , uses different infrastructure.

** A few days later **
I tried the second more expensive sim, with rabbit ears, in a better position in the house, and I got 75 download, 30 up and 4G+ LTE.
Despite this setup actually performing the worst in the video, It is the best and outperforms what I could get using the dedicated antenna.