Questions about Series 9

I only clean the device when I have to charge it. Currently, with the new battery, this is the case about every 14 days. o Considered, the cartridges last a long time. I also clean them after use, let them dry and refill them with a much cheaper replacement product from the internet. Works flawlessly for years.
Opinions differ as to whether this device is the best Braun. In any case, the much more