Thank you for your thoughts, I've actually been waiting for someone with a lot of mileage on the Sigma to compare the two . You're not the first one to say the Sigma is a bit better on the wide end either...
I’ve used the sigma for two years daily and Sony gave me a loaner of this. I’d say the sigma rendering is a bit nicer, more prime like and I’ve never had sharpness issues. The Sony is much nicer to handle, it’s light enough to go around your neck, the af is noticeably better, especially with subjects coming at you fast and close and obviously you get faster fps if you need. Mostly amazed at the size and weight. So… it probably depends on your uses.
. You're not the first one to say the Sigma is a bit better on the wide end either...