Generally, I advocate that the width of the floorboards should be in proportion to the size of the space. So many of the homes in the Salt Lake area are bungalows with divided rooms and low ceilings - wide plank boards feel out of proportion. But there was something about the architectural style and tall ceilings in this downtown Salt Lake 1 bedroom home that lent itself to a wider plank - giving the home a New England farmhouse type feel. We did a 7.25" live sawn (also call European) white oak with a clear water-based sealer.
The other fun element on this project were the weird transitions. When the homeowner bought this home, there was a 2" height difference between the living room and kitchen and the back room was a converted porch, so we weren't sure what that transition was going to look like. We removed 4 layers of flooring in the kitchen (!!) and then re-sheeted the living room, bedroom, and kitchen to increase the structural stability of the subfloor and get the kitchen flush with the back room. In spite of all of my warnings to the homeowner that there could be some transitions since we weren't sure what we were going to find, we were able to get the wood floor to run seamlessly throughout the main level of the home!