If you insist on alkaline batteries you will severely limit your options. Rechargable lithium ion batteries have so much more power. Lithiums hold a charge well, and you can always just have a spare set. When I go for a night hike, I just take the light, and throw a spare battery in my pocket. The size of my light is about the size of a cigar tube, and puts out about 5 times more light than a 3 D cell LED maglight.
Surefire is kind of the king of the hill and very pricey. Fenix, Nitecore, Olight, and Streamlight ( and others )are probable the next tier. NEBO is a new brand that is advertising heavily. I would avoid them. When you look for a light you want to make sure its rated according to ANSI FL-1 standards. The specs will be displayed in a format that gives credibility to the specs. If a light just says "1000 Lumens" don't believe it unless it is presented in that format.
I have never used the marinebeam, but would guess from the amount of text they devote to justifying its low lumen output that it's not a great light. The narrowness of that beam is going to make it more like a laser than a flashlight.
For some people flashlights are like watches. A Timex will be more accurate than a Rolex, and if all you want to do is know what time it is, the Timex is probably a better watch. If you are a diver going down to 100 feet or more, the Timex won't cut it.
Brightguy.com has a great search feature where you can search their inventory by parameters like distance, battery type, price, modes, and more.
https://www.brightguy.com/shop/long...istance=number&rng_order_pa_beam-distance=ASC
Here's an example of a Nitecore long distance at the same price point as the Marinebeam:
https://www.amazon.com/Nitecore-MH4...80069772&sprefix=nitecore+mh40,aps,159&sr=8-3
This would be a FAR superior light with more useable output, more features, and a more useful beam profile.
Candlepower forums are a great resource, but also remember it is a forum similar to this one in that there is no shortage of personalities, opinions and biases.
Lastly.....if you have cordless tools, check to see if whatever platform you have for tools has a spotlight. I have a milwaukee 12 volt 750 lumen spotlight that has a beam distance of about 700 yards and that uses my cordless drill batteries. Its a solid light and is only about 70 bucks.