So it costs 2x more [than a 320], performs the same, but gets you up to an order of magnitude more endurance. The question then is: when are you planning on re

So it costs 2x more [than a 320], performs the same, but gets you up to an order of magnitude more endurance. The question then is: when are you planning on replacing it. If you are going to replace it within the lifespan of a 320 (maybe for more capacity, or because new generations will be faster), you are better off sticking with a 320.