nobd, what kind of photography do you like to do most? or where do you do most of your shooting? indoors, outdoors, night time, etc
85mm is pretty close to 100 but they both have different uses. i own both a 85 1.4 zeiss and 100L macro. the canon 85 1.8 is probably the best lens canon offers in terms of value. if you like to shoot portraits, especially women, then the 85 1.8 is gold.