the most obvious improvement is the sharpness, being a prime this lens is incredibly sharp. it was the very first thing i noticed when i attached it to my body, and then focused on my girlfriend, her eyes were crystal clear, more-so than any other lens i have. the focus is silent, however it tends to hunt, so i usually use it on manual focus. obviously the kit lens has the versatility of being a better walk around lens. but being 58mm i was able to use my circular polarizer with both. i think that this lens was probably one if not my best purchase for my camera. for the price, i don't think you can beat it. (hope that helped, and thanks for the compliments
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