Here’s my setup and I have been happy with the results.
Bambu Labs X1C with AMS “dryer mods” using activated alumina. I’m using Sensor Push sensors which can measure humidity levels from 0 to 90 plus. The sensors alert me whenever the humidity levels in the AMS go above 5%.
Both my PA-CF and PAHT-CF I’m currently using has been stored in their respective AMS units for 3+ months.
With this setup, I’ve never had to dry any of my filament before printing.
Here are some pictures showing the setup along with some test prints.
As an aside, I calibrated one the Sensor Push humidity sensors using 32% calibration test packs. I then calibrated the other sensors using the calibrated one. All sensors were within 1 to 2% of calibrated sensor and the app allows you to add the calibration adjustment if wanted. I also tried Govee and Tempi.fi sensors which worked well, but the Govee sensor embeds ads in their app, and the Tempi.fi app was good but not as a good as the Sensor Push one.
I stopped using the sensors everyone typically uses (i.e. rectangle or round ones). All are rated at best down 10%, although a surprising large number of them won’t read much below 20%. Bad news is the all the connected sensors are relatively expensive. If I recall $75+ USD. Maybe not bad for 1 AMS unit, but if you have 8 of them it adds up.
I also found some 5 to 15% humidity test cards which allows me to sanity check that the sensors were in the ballpark. These cards are typically used in electronics packaging and are available through large electronics distributors but in a pinch can be ordered from Amazon (US) as well.
I’m super happy with the setup. My only real wish would be that changing out the activated alumina was easier. In a perfect world you wouldn’t have to remove the spools to change activated alumina which for 8 AMS units ends up taking a chunk of time. Toying with the idea of creating interchangeable desiccant packs that can be plugged in and removed from the front of the AMS of units. This though would require a fair amount of AMS “dremel mods” though so yeah … probably not happening any time soon. 
Although maybe BL will see this and make updated AMS units … PLEASE PLEASE PLEASE!
Hope this helps…
D