I'm 178 too but with 88cm inseam.
Had the same in-the-middle issue, and did choose the 19".
It had about the same sizes (especially the stack/reach) of my previous bike that wasn't giving me any pain or discomfort.
With a 90mm stem, and a seatpost with 2.5cm back offset.
The bike fits perfectly(knees just over the pedals. No pain after long rides, etc.)
I'm near Brussels.
A shopping distance for our US friends.
But another country for us
Let me know if you'd like me to take some real measurement dropping the seatpost for 5-7cm.