hey i will agree the 18-55 IS is sharp, but i need something sharper and perform well in low light condition, which the 17-55 f/2.8 IS USM delivers. i haven;t seen any sharper image thru the 18-55 IS. on the other hand, one cost at least 7 times the price of the other, hence for 'not-so-serious' ppl it'll be sufficient. Even dpreview.com recommended the 18-55 IS. After you got the ferrari, will you still look back at your toyota?