What are the disadvantages of fast charging over slow charging?
Yes there are some factors to take in to consideration when comparing fast charging versus slow charging, but basically as long as you have a good quality charger that does not literally fry your batteries, it all boils down to your needs and preference. Basically to use a simple analogy, fast charging is sort of like when you drive your car at higher speeds, you get to your destination faster but there is a little more wear and tear on your vehicle. However on the other hand when you drive your car slower you will get to your destination a little later with less wear and tear on your vehicle. But in the end the differences won’t matter much. NiMH batteries, like your car, will normally have a longer useful life if they are not abused, and are charged using a good quality charger, whether or not it is a fast or slow type charger.