Is the Sigma 70-300 DG Macro APO really that bad?

I've been looking to buy a 70-300 lens to have a go at telephoto landscape shots, and this seemed like great value for money for someone like me who isn't monetizing my photography, especially since I have both a Canon and Sony body, and have been looking at Sigma lenses + MC-11 as a solution.Online reviews don't have much good to say about this lens though. I get that this is definitely not going to match up to Canon's much pricier 70-300, but is it really unusable bad, or is it just technically bad when you pixel peep, but out in the field you'll still get decent images? via /r/photography http://ift.tt/2tw45ie