I'm not suggesting there weren't great strides taken in the past decade with golf equipment, but with certain limits put in place by the USGA there was really only so much room for improvement. Sure, my Callaway FT-3 driver nets me 5-to-8 extra yards on average compared to the Titleist 975-D I was using back in 2001, and my new Titleist AP2 irons are much more consistent and controllable than the Ping i3 blades I used previously. The golf balls are supposedly better too, although back in 2000 the Pro-V1 was already immensely popular and the only real difference I've noticed in general is that balls tend to be a bit more durable now. All of these little improvements add up, of course, and have probably shaved a stroke or two from my average round, but it was the addition of the SkyCaddie SG5 to my game that had the most obvious and immediate impact.
The SkyCaddie's usefulness was apparent not just from situational observations, but could also be measured statistically. I compared the 15 rounds I played before using the SkyCaddie SG5 to 15 rounds using the device, played on the same courses in similar conditions. My average round improved from 78.7 to 77.1 and I hit approximately one-and-a-half more greens in regulation per 18 holes. While an improvement of 1.6 strokes per round may not sound like a dramatic difference to some, for a golfer with a 4 or 5 handicap like myself, it's huge. I suspect golfers with higher handicaps will experience even greater results.
Many players have dismissed GPS units by pointing out that most on-course measurements to the center of greens are fairly reliable nowadays. Whether that's actually true or not, they fail to recognize three key advantages the SkyCaddie SG5 provides:
1) Accurate spot-to-green measurements from anywhere on the course, not just the fairway or close to it. So if you hit your ball deep into a grove of trees or onto the fairway of an adjacent hole, you can still obtain an accurate distance without having to eyeball your best guess from the nearest available marker. My personal feeling is that this feature is where the device is most likely to save you strokes.
2) The distance to the front, center and back of each green, which is the kind of crucial information that professionals receive from their caddies but the average golfer does not (sadly, yardage books are not as widely available at courses as they should be). In numerous cases where I was in-between clubs, I found that knowing the distance to the back of the green allowed me to take the longer club and swing with more confidence, knowing that if I struck the ball perfectly it still wasn't likely to fly over.
3) The distance to hazards and other significant points of a hole before the green, such as where the fairway ends if there's a gap. It's much easier to determine whether you should attempt to fly a bunker from the tee if you know how far you need to carry it, and it's significantly easier to lay-up on a par 5 and leave yourself the optimal wedge distance to the green if you know how far you should hit it. These types of measurements simply are not available in most cases, and even yardage books tend to document them poorly.
Perhaps the most underrated advantage of using a GPS device is that it causes the player to address each shot with a more analytical approach, the same way an actual caddy feeds data to a tour pro. Most instructors and players agree that the worst thing a golfer can have in his mind before a shot is doubt or a lack of confidence (which more often than not involves club selection), so any tool that helps to alleviate these feelings can only be beneficial to your game.