My yeasted ciabatta comparison

Wow!  I was surprised today at work with the texture of this bread when I finally ate some.  I've never worked with a 'biga' before, and my first visual impression was that it was just a normal loaf of bread.......This was the lightest, softest bread I've made so far.......In comparison with the sourdough ciabatta, I would have to say that the judgement between the two would be really subjective.  The sourdough was a little heavier, more substantial texture...but still very light.  The ciabatta with biga was a big hit, but probably no so much with the texture.....the mushrooms, serrano, garlic, and cheese I added to the dough probably elicited the most responses....Also, I think my co-workers probably really like soft bread...which the ciabatta/biga is very, very soft.....

I haven't mastered the flat dimension of the ciabatta dough......my sourdough and biga versions both had good vertical oven spring.  After reading Reinhart's comments on Ciabatta (stating that there are so many poor commercial versions of ciabatta), I'm not even sure I've made good ciabatta bread yet.  My attempts are very good and tasty to me, but I'm not sure they are good examples of ciabatta.  Both my attempts have produced very soft and tender crumb.  I'm not complaining, I'm just not sure these are good examples of authentic ciabatta???? 

I put the photo of the sourdough ciabatta first, and the biga ciabatta second.