The Life X2 has a fast charge feature and comes with a high amp charger. I don't need the fast charge. Will I extend my battery life if I use a slower charger?
Technically, yes, but in real world usage, you probably wouldn't notice that benefit unless you kept the phone for more than a couple of years. Since most people tend to upgrade their phones every 2 years or so, these strategies usually end up being not very useful.