"I am interesting about 4.0/100-300"
Popular Photography reviewed this lens a few years ago. Like many of their lens reviews, one has to read between the lines. At 300 mm. it has peripheral softness. One has to stop down to f16 to get edge-to-edge sharpness at 300 mm. Clearly this requires a tripod. That weakness dissuaded me from being interested in it.
For wide angle, I highly recommend the FA 20-35 f4. You will pay a lot for it, but you will never regret it.
Joe
