I recently purchased a 40D with the 28-135 kit lens.
My primary purpose for the purchase was to shoot my daughters martial arts competitions which normally take place in typical high school gym lighting with no flash allowed. Knowing full well that the kit lens would be unsuitable for this purpose, I also purchased an 85mm f/1.8 and an 17-55 f/2.8. The combination of these two should be sufficient for this purpose, and I could add additional primes if needed.
However, my camera use is certainly not limited to martial arts. I'd like to take it out and about for whatever I find interesting. The 17-55 will certainly work well for family gatherings, indoors and out, and even the prime lens would work well. I've tried walking around with the kit lens and find the reach too small to capture the occasional wildlife or bird photo. I'd like to sell the kit lens and replace it with a reasonably inexpensive tele zoom. This is not the primary use, so I can't currently justify the costs of the various 70-200 L lenses. Perhaps the non-IS F/4, but I think the IS would be beneficial, so I was looking at the 55-250 IS or the 70-300 IS lenses.
Has anyone here used either or both of these lenses and can share their opinions?
I'm open to other suggestions, but I'm trying to keep the cost around $500 or less.