What They Have in Common
Both are Nikon rangefinders with 6x magnification, slope mode with a legal toggle, first-target priority (so it locks the flag, not the tree behind it), and the Locked-On Quake vibration feedback when the target registers. Both run on a CR2 lithium battery, which you can find at any drugstore. Five-year warranty on both, which is longer than most competitors offer.
Where They Differ
Accuracy and Range
The 20i GIII is accurate to ±1 yard up to about 109 yards, then drops to ±2 yards beyond that. For most approach shots into a par-4 green, you're fine — the difference between 147 and 149 yards isn't the variable that's killing your score. The PROIII STABILIZED holds ±1 yard across its entire range, all the way out to 1,200 yards. That extended range won't matter on most public courses, but the consistent accuracy might, especially on longer approaches where dialing in to the exact number matters more.
Image Stabilization
Here's the thing that actually separates these two in real use: the PROIII STABILIZED has image stabilization, the 20i GIII doesn't. If you've ever tried to steady a rangefinder while holding your breath and hoping the number locks before your arm wobbles, you know why this matters. Stabilization makes targeting faster and more reliable, especially at distance. Nikon also rates the PROIII at a 0.1-second read time. That's not a number you'll consciously notice, but the experience of point-and-lock versus point-and-wait is real. Probably the biggest practical difference between the two.
Display
The PROIII STABILIZED uses a red OLED display with auto brightness. An OLED in a rangefinder is noticeably easier to read, especially in low morning light or when you're in shade and the numbers need to pop. The 20i GIII uses a standard internal display, which is fine in most conditions. Nobody reads a rangefinder in direct sunlight if they can help it — they shade the lens with their palm — but when you're playing early or late in the season, display quality starts to matter more than it does in July.
Water Resistance and Weight
The PROIII STABILIZED is rated IPX4, which means it'll handle rain and spray without worrying about it. The 20i GIII is listed as rainproof, which is a softer designation — fine for most rounds, but I wouldn't soak it. The trade-off is weight and size: the 20i GIII is 4.6 oz and genuinely compact. The PROIII is 7.2 oz, which isn't heavy, but you'll notice the difference after a few hours on the bag.
Who Should Buy Which
Get the COOLSHOT 20i GIII if:
- You want a rangefinder that fits in your front pocket without thinking about it — the 91 × 73 × 37 mm profile is legitimately small
- You're a mid-to-high handicap player who wants slope and accurate yardages without spending $500
- You're buying your first non-budget rangefinder and want Nikon build quality without committing to a flagship price
- You're the golfer who plays 25–30 rounds a year at the local muni and needs something reliable that won't break the bank
Get the COOLSHOT PROIII STABILIZED if:
- You play early morning rounds regularly and dim-light display readability actually affects your game
- You want stabilization — if you've ever had trouble locking a target at 175+ yards, stabilization is a genuine quality-of-life upgrade, not a marketing feature
- You're a single-digit handicap who cares about the difference between 162 and 164 yards and wants that ±1 yard consistency across every distance
- You play in variable weather and want IPX4-rated protection, not just "rainproof"
The Bottom Line
The 20i GIII is a solid rangefinder at a fair price. But the $280 price gap goes toward things that show up every round — stabilization, a cleaner display, consistent accuracy, and better weather protection. The question is whether those upgrades matter enough to you to justify the cost. For a lot of golfers, they don't. For a golfer who plays frequently, cares about precision, and wants to carry one rangefinder for the next five-plus years without second-guessing it, the PROIII STABILIZED is worth the stretch. I'd go with the PROIII if the budget's there. If it isn't, the 20i GIII won't leave you frustrated.
Get the Nikon COOLSHOT PROIII STABILIZED.
See Also