Originally Posted by shoota

Great questions.
I just took them off and put them on my steel allroad bike that sees mostly pavement. Replaced them with Trigger Pros.
For gravel, even though they measured 38mm on these rims, there still wasn't enough air volume in them. I really needed the 38mm version.
I got the + because it was the only version my shop had, and this was an experiment. They are ever so slightly stiffer but they felt as fast as any gravel tire I've ever used, except for the Terra Speeds.
For Iowa gravel I would recommend the 38's in the non-+ casing. They're fast and grippy.