Not sold it yet then Chris?
(In advance clengster, dontcha just hate it when folks like me throw in more options!)
Have a good old snoop around at reviews; by now much has also been made of the Sigma 10-22.
I have to say, that "kit lens" is pretty decent at the wide end too.
The Tokina would give you a little more overlap of focal length.
I found my "solution" to be a compromise: I decided to just ignore my kit lens and build from the wide-end up. I chose the 10-22(Wedding Shooter and others will testify to its quality) knowing that I'd crossed the Rubicon in terms of pumping a bit of cash into the "x1.6 crop format". Had I let my kit gather dust until Canon brought down full-frame to realistic prices, I''d have still eschewed the 17-40 in favour of primes.
You might have to make a couple of decisions, based on image quality versus convenience, also on whether you intend to stay with this sensor size or move to full-frame.
The Canon 10-22 may or may not be "worth" it, compared to to the Tokina/Sigma, depending on your own parameters. I'd guess that on a 350D the benefits of "L glass" would not be glaringly apparent, though I stand corrected in advance if others testify to the opposite.
One other general thing: photoforums are the fertile breeeding-ground for all sorts of elitism and pseudo-mysticism. Phrases like "L glass", "astonishing" and "bokeh"(yuk: who heard of this word until a couple of years ago?) are rattled off by folks who never get an image off their pc, and who get off on being able to spend more money than other people. Just decide what your output size and audience are going to be, then sum up the choices: Jules says it really: decide which is more important for you. Then enjoy. That Tokina does sound nice though, and maybe a better bet than the 17-40 for this camera and the type of work you're considering.
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