3 Questions re Canon 15-85mm USm IS Lens

Thanks for the answers.

Here is another question I just came to think bout, because I am looking into close-up photography:

Do you have any experience with the Canon 500D Close-Up lens/filter and the 15-85mm lens?  If so, share with me, please.

My alternative is to buy the Canon 60mm macro lens.  But, I do not know if I really need it to take close-ups of flowers in my kitchen with use of a tripod.  Any thoughts?