As the 420 is the older model, and it was higherpriced than the 430, it sounds like KEH may have a mistake on their website, or they are not willing to sell for less then their cost to move the older inventory, but as far as more or less features, the 430 has a bit more whistles and bells than the 420 and if it is that much lower, I would definately purchase the 430, which is a very nice flash, I sold a heck of alot of them when I used to work in the photo store.