Just got this lens today, along with some other general crap I needed for gear.
For beginners, this lens is a steal at $299. Took some quick test shots, and looking at the results, I am pleased with it's sharpness. In fact, I'm shocked. I'm by far not the steadiest of hand, and the out of focus areas are not nervous looking. Is this because of it's circular aperture blades? I don't know, but I can't wait to shoot the car, along with some street photography with this. I'll be posting some tripod mounted newspaper shots at different focal lengths later, just to see how sharp it is corner to corner.
The following pic was shot handheld, IS on, wide open aperture at ƒ5.6, fully zoomed at 250mm, and a shutter speed of 1/125. Camera Picture style settings: Neutral (contrast: 0, tone: 0, saturation: 0, sharpness: 0). Adjustments to sharpness made on Canon's DPP software, which pretty much is what you'll have if you adjusted sharpness in camera.
Resized with DPP. Settings on camera:
Neutral on picture styles (every on picture style setting on "0").
100% crop with DPP. Settings on camera:
Neutral on picture styles (every on picture style setting on "0").
100% crop with DPP. Settings on camera:
Neutral on picture styles (every on picture style setting on "0" but sharpness set to 5).
100% crop with DPP. Settings on camera:
Neutral on picture styles (every on picture style setting on "0" but sharpness set to 10 [max]).