The Quick Verdict
Get the Bushnell A1-Slope. It's $60 more than the Nikon, but you get a meaningfully better accuracy spec, USB-C recharging, and a stronger water resistance rating — and that gap adds up over a few seasons. The COOLSHOT 20i GIII makes sense only if you know you play in dry conditions and would genuinely rather deal with batteries than a charging cable. Check price at TGW →
What They Have in Common
Both are compact, pocket-sized rangefinders with 6x magnification, slope mode with a legal-play switch, and ±1 yard accuracy at shorter distances. Neither is going to embarrass you on the course — they lock on a flag, give you yardage, and stay out of your way. That's the baseline, and both clear it.
Where They Differ
Accuracy at Real Golf Distances
Here's where the gap actually shows up. The Nikon's ±1 yard spec only holds to 100 meters (about 109 yards). Beyond that, it widens to ±2 yards. The Bushnell holds ±1 yard out to 350 yards — which covers nearly every approach shot you'll hit. For a wedge from 80 yards, neither difference matters. For a 6-iron from 190, it does. Not dramatically, but you're paying for a rangefinder to give you good numbers, and the A1-Slope gives you better ones across the distances that actually matter.
Battery and Recharging
The A1-Slope uses USB-C and is rated for 50+ rounds on a charge — around 3,000 actuations. You top it off like your phone. The COOLSHOT 20i GIII runs on a CR2 lithium battery, which means you'll eventually need to replace it. To Nikon's credit, CR2 batteries are easy to find, and a fresh one lasts a long time. But there's a real difference between "charge it Sunday night" and "remember to buy batteries when you notice it dying on the 12th hole." Probably comes down to how organized you are, honestly — but the USB-C option is objectively more convenient in 2025.
Water Resistance
The Bushnell is rated IPX6, which means it can handle a direct water jet — real rain, a cart wash, whatever. The Nikon is listed as "rainproof," which is a softer claim. It'll handle a drizzle, but I wouldn't count on it through a full downpour. If you live somewhere where afternoon thunderstorms are part of the golf calendar, that distinction is worth caring about.
Range
The A1-Slope measures out to 1,300 yards. The COOLSHOT tops out at 800. In practice, you're almost never ranging more than 350 yards on a golf course, so this rarely matters. But the 800-yard ceiling is tighter than most competitors at this price, and it's worth knowing.
Who Should Buy Which
Get the Bushnell A1-Slope if:
- You want the most accurate yardages across full approach distances, not just short shots
- You play early-morning rounds in wet conditions — IPX6 is real protection, "rainproof" is a marketing qualifier
- You want USB-C charging and the ability to just plug it in with the same cable as everything else you own
- You're buying one rangefinder and keeping it for several years — the build and battery system hold up better long-term
Get the Nikon COOLSHOT 20i GIII if:
- You play mostly in dry climates and weather protection is genuinely irrelevant to your situation
- You're the kind of person who keeps a spare CR2 in their bag and prefers not to think about charging — you're covered without ever plugging anything in
- The $60 price difference actually matters to you and you play mostly inside 200 yards where the ±2 yard accuracy difference doesn't show up
- You want a lightweight option — at 4.6 oz, it's half an ounce lighter than the Bushnell, which is a small but real difference if that matters
The Bottom Line
The Nikon COOLSHOT 20i GIII is a decent compact rangefinder, and the five-year warranty is genuinely good. But the accuracy spec degrading past 100 meters is a real concession, and "rainproof" leaves more to chance than IPX6. The Bushnell A1-Slope is $60 more, holds its accuracy out to 350 yards, has real water resistance, and recharges over USB-C. Across a full season — or two or three — that's the better tool.