I've moved to the wide 44 bars on my last 2 bikes. I'm large built, with wide shoulders and a big chest chest so the extra width feels better and allows me to feel as if I am breathing more freely. (I know the few cm aren't really opening things much, it is the way it feels in my mind.) As far as stem height and length I have lowered my stem and turned the angle down as I have gained flexibility and lost weight. I have a 100mm length stem, a Cannondale C3, with a single 25mm spacer between the stem and headset cap. That is being changed this week, possibly today if I can get things sorted out, cutting that down to between 10-15mm whichever feels best riding. Bar shape is a shallow, non-ergo bend drop, a Cannondale C3, that feels good with easy reach for the brifters. Tape is Specialized Roubaix cork.

I ran a 38 width for a long time and a fairly long stem, both quill and thread-less systems, and a deep drop. Now the shallower, wider bars fall just right. It took a few trial and error fittings to find the set up for me. it was worth the effort and time.

Bill