I just purchased my first DSLR. I bought the canon rebel XS kit. I was told by a friend of mine that the 18mm-55mm lens that it came with was crap. For a stater lens I was looking at the Tamron Autofocus 28-80mm f/3.5-5.6 and the 70-300mm. Like I said I am new to the photography game but I would like to know if these are good lenses for a starter.