So, I've picked up this camera stuff as a beloved hobby, and thoroughly enjoy it far too much. I've got a Canon 5D Mk II and a 7D, and am looking for an EF lens to go on them. I'm pretty fussy about wanting expensive glass, and good aperture, and up until now have been very Canon glass biased. Anyone got any recommendations of decently priced wide angle though? More for group shots than anything else.