I've only used the 10W iPad charger for years on iPads and iPhones. The charging speed is faster than the 5W iPhone charger. I don't have exact numbers but I feel like it is 25% or more.
Fast charging ruined both my previous iPad Pro 10.5 devices.
And from what I’ve read, the people witnessing the most battery degradation with their iPhone X are those using iPad 12W and 29W chargers. While those witnessing the least degradation are the ones using wireless charging or the 5W charger.
Disagree. And I doubt most consumers charge their phones from 0% to 100%, it’s more likely somewhere around 30 or 40%, which iPad charger sufficiently does so in an adequate amount of time.
I've been using a 12W iPad Air charger for the past three years to charge my phone. As for Wireless charging, I've been using a Samsung Fast Charger. I know it's not really fast charging my 8+ because I'm using the plug that it came with because I also use it to charge my Android phones but, it still charges fast enough for me especially if I put my phone on it over night.
There are times I will leave my phone plugged in for an entire weekend and it's never harmed my battery and I've left my phone on the wireless charger for a weekend as well.
I say just charge your phone however you are used to doing it and live your life. The phone will be fine.