They both seem overpriced to me. It really depends on your area. I see alot of good deals in larger cities. Get away from large metropolitan areas and the prices go up. Less to choose from.

If you get a bike that fits, you will be much happier. Getting a bike that is too large and then lowering the seat, doesn't make it fit.

I have similar measurements as you. I bought a 56. At first it didn't seem any different than a 58. After a few hundred miles, I was glad I got the 56. After a thousand, there is no way I would buy a larger bike.

Have to try it out for yourself. I realize a 56 is a 56 is a 56, but I believe some brands vary slightly in their dimensions. It could be a slight variance in the geometry. This is a subject that goes way beyond my knowledge.