[OnePlus 9 Pro] LormaD:
I got my hands on a One+ 8T 5G and loved it. It was fast (on 5G in Canada) right out of the bat, smooth, snappy and bug free. I did root it, and debloated some T-Mobile stuff and had an opportunity to move on to One+ 9 Pro 5G LE2127 T-Mobile.

As a stock out of the box smartphone, the LE2127 is hit and miss. Most of what I didn't like I could fix and improve, some, I couldn't. I unlocked the bootloader, rooted the device, modified the policy restrictions and debloated. All of this improved the smartphone, but as an out of the box smartphone there is not a lot to improve upon if your NOT in Canada.

I was disappointed with the performance of the device on the 5G network. Yes, the handset would say that it connected to a 5G network, but many times it was a 4G LTE tower despite the handset showing the 5G icon. The truth was in the pudding, the connection speedtest on the 5G Network were on average 50% less than the comparable out of the box working One+ 8T 5G. And for what it's worth, I could not get the device to convert to the global LE2125 image (I tried a half dozen times, not wholeheartedly because I failed). What really irked me was the subpar service red tape mumbo jumbo that this device has if you are not in the USA. In Canada, it's a caveat buyer beware hate hate relationship.

I am now running a true global One+ 9 Pro LE2125 handset that you CAN unlock the bootloader without the 7 day wait period that you must endure with the LE2127. From there I refused to take the upgrade to Android 12, and I only modded the policy restrictions so as to access the 5G Network in Canada (therefore, not rooted, not bootloader unlocked). Once again, I was disappointed with the results and performance.

So I stumbled upon this... I decided that if I was going to unlock the bootloader, I would need to format and start all over again. So that is what I did, I decided to unlock the bootloader and set up my device and take all the updates. I can't say on the surface Android 12 is better than Android 11, but then I can't say I am experiencing any issues or bugs. From there, I then followed the guide and decided to root my device and install one of my favorite apps, Adaway.

To my dismay, I found out that I could not mod the policy restrictions because I could no longer access engineering mode. The following also did not work *#*#4636#*#*. And worse, the handset no longer showed 5G as an available option in the "Preferred network type" Aw cr@p!

But, to my surprise, I did try 5G switch from the playstore and it worked (allowed me to choose NR and therefore my device accesses the 5G network type). But better than that, the actual performance on the 5G Network running Android 12 w/ 5G Switch is a lot faster than using the SAME handset on Android 11 w/ the Policy restriction mod on the 5G network. You might want to consider this route if 5G is important to you.

So far, I have not had the time to investigate whether or not you can access the engineering mode on Android 12 (so as to permanently mod the policy restriction file in order to access the 5G network), nor whether or not you can debloat some of the LE2125 global bloatware.

All this to say that I am more satisfied running this configuration (Android 12, bootloader unlocked, rooted, 5G Switch) on my device.

Cheers