These are great photos. I really like the macro shots you guys/gals get. I'm looking to get a Canon Digital Rebel or 20D. Not sure exactly what I can get away with my wife yet. Hopefully the 20D! Either way I'm sure to be on a budget for the extras. I was looking at the Canon 50mm lens at Ritz.com for $319.50 and then decided to come do a search here. The Sigma 50mm lens is $249.99. That's a $70.00 difference. Would you guys think this would be a good place to save money? What disadvantages, if any, will I have with the Sigma Lens?
I have no experience with the macro lenses in question, but I did purchase a Sigma 20mm lens over the Canon version, and I have been very happy with it. It actually had better specs than the Canon lens.
One resource that I've found invaluable in researching camera lenses is PhotographyReview.com. They have a number of reviews for the Sigma 50mm macro lens.
Also, check out BestPriceAudioVideo for the Canon lens. They have a better price than Ritz -- $251 w/ shipping. Of course, they're out of stock.... Or try B&H for $249 + s&h, in stock.