Make sure you read and research before investing in this lens. It is quite different beast from the rest of the EF line and not necessarily easy to use. The results are amazing but it takes a lot of practice and learning
* To get the best out of this lens, you'll need to invest in a light pac specifically designed for macro work. A ring light is one popular choice.
* I HIGHLY recommend getting a very stable tripod that can establish low height as well as move the center column horizontally.
* I HIGHLY recommend that you get a macro rail attached to a good strong head. Remember this is a true macro that you focus by bringing the lens or subject closer or farther away from the lens. The only way to do this with accuracy is with a rail.
* Also remember this is a manual focusing lens... your dim viewfinder on the Rebel isn't going to help focusing. In this sense, it isn't a true EF lens. The lens is very dark by 5x.
* Working distance can be tough... especially with things like insects.
In the end, most people (except for the most serious photographers in macro) will go with the 100mm macro or the 180mmL macro. They are closer to what photographers think of with they think dedicated macro... close focusing distance... autofocus operational.. and can be used for other non-macro work.
I played around with it for a while (when I had access to one) and I determined that I wasn't "that" dedicated to macro. Traditional lens attached to a bellows unit and/or 100mm for less than 1:2 stuff was more than enough to keep me happy.