The Stren says on the packaging that it has a .22mm diameter and the braid says .15mm diameter, so the braid is 30% smaller than the Stren, but when you just look at them in your hand, side by side, the braid looks bigger.
It has to be because the braid is more of an opaque white and is reflecting more light. It might be smaller in diameter, but it is definitely more visible.
For me, right now, the issue is line visibility, learning to see those tiny pressure strikes, so it has to be easy to see above water. I'd also like to avoid leaders, and I have a feeling the Stren might fit the bill, but the braid is probably going to need a leader.
Anyway, I was really surprised at how the larger Stren actually appears smaller.