Hello all,

I would like some information. I am thinking of purchasing a Sigma APO 100-300mm F4, EX,
DG HSM lens. I have looked at reviews & I think the positives out way the negatives, but in saying that I would like your input before I lay out the money.

I was also thinking of getting either a 1.4 or 2 x extender for the lens if I get it (that will really blow the budget). I would also like input in regards to these extenders as well. I have a Canon 450D, & understand that Canon make these lenses as well, but like most things, it's additional cost of the brand name lenses.