Led not working is common with any linux wifi driver, as for speeds, you can set preferred connection speeds, but they often default to 2.4 Ghz which has better range but is slower, opposed to 5Ghz which is faster, but doesn’t travel as far. The driver that is installed by default supports monitor mode, the driver you want to install won’t so you won’t be able to use it for scanning.
https://askubuntu.com/questions/1058622/how-to-force-to-linux-to-connect-only-5ghz-channel