My take on Zebra H30, H31 & SC 30 (just my opinion)
I have been using the Zebralight H30 for a little over a year now. I absolutely love it and have heavily recommended it and have had many friends get it and love it also. The light is a wide angle flood with no hot spot or shadows or irregularities anywhere in it. It lights up a large area in front of you without the typical swinging of the head to get the brightest light on an object that seems to happen with a light with a hot spot.
I just got an H31 in hopes it be a similar beam quality just a bit more narrow and brighter. Although very bright, it does have a hot spot that significantly narrows the useful light. I tend to focus on the area of brightest light which causes a loss of peripheral vision and I end up having to move my head allot more rather than just my eyes. It is great if your desire is for more throw. It throws a good long way for a headlight but that is not my objective. I typically carry a flashlight also and use it if I want to throw light on something in the distance momentarily. Another consideration for me is I want to use as little light as possible so my eyes are not straining to adjust between the darkness and the light that I am using. I typically like to throw allot of light when looking off in the distance so the H31 doesn't really work for that because although bright, I prefer more light and more range for distant threats to my well being. When I use a bright light to investigate something in the distance, I try to limit the runtime as much as possible so my eyes don't begin to adjust to that light effectively leaving me somewhat blind while they adjust back to the headlight. It also does not have a brightness level that suits me. It is either a little too bright or not quite bright enough. Enough on that!
As for the SC30, I got them to set up a 600 lm Headlight rig. I wanted the ability to really light up an area if the situation called for it so I was going to put one SC30 on each side of my head facing forward and one H31 in the middle. It was a good idea and they all fit comfortably on the headband, but if your head is shaped like mine, there is a crook in the back that is the obvious place where the headband rests comfortably and that is lower than the comfort spot on my forehead so the SC30's point skyward in a totally useless direction and can not be adjusted down. This is all just fine because I am used to failing as often as I succeed! Keep in mind that none of this says anything negative about the light itself, I am just not sure how they intend for it to be used as a side mount headlight when it is nearly impossible to get it to point at the ground in front of you. The SC30 makes a fine EDC if it is appealing to you for that use. If it is, you can buy one or both of mine (light only No headband) for 40 ea freight included.
That's all for now. Hope it will help someone with a decision they are trying to make. Good luck!