1.6x FOVCF is due to the size of the sensor in the body. That said, 1.6 FOVCF is necessary (as is the white square on the lens mount) for EF-S lenses - the mirror of a 1.0 or 1.3 FOVCF body would hit an EF-S lens.


Back to your lens questions, if it's your honeymoon, rent! Don't worry about investing for the trip, rent to have good stuff with you, and use it as a learning experience to decide what to buy later. My fiance and I have a decent assortment of gear, but it's been a well-known fact that we're renting some more goodies for our trip in September. I don't know where to go for rentals in the UK though.


I have heard disappointing things about the 15-85. The 18-55 IS is a good little lens, but probably not much of a step up for you. 10-22 is incredibly fun.