For everyone who golfs semi-regularly/regularly, I think that a rangefinder would be a good investment. It is always nice to go to a course that has the GPS preinstalled on the cart; however, what I have learned is that these are not always as accurate as they seem.
The Callaway 200 Rangefinder has now been discontinued, but if you can find it somewhere still, I would recommend it. It is a relatively affordable rangefinder, and it does a good job of making it easy to accurately measure the distance. While there are plenty of rangefinders that are $300-400+, these ones are probably too fancy for an amateur golfer; I feel like any rangefinder that is convenient to carry and can easily give you an accurate measure of the distance to the pin is all you need.
I personally use the Callaway 200 Rangefinder, but I think that most rangefinders nowadays offer similar features. In order to differentiate themselves, the more expensive rangefinders offer features such as farther zoom, magnification, etc.; however, there are no 2000 yard golf holes, so any zoom past 500 yards does not really make any practical difference.
I am personally not a great golfer (handicap of 15 or so), but having a rangefinder does help me; at least now when I am on the golf course, I only have to worry about hitting the correct distance, and I do not have to worry about wondering if I am choosing the right club or not. Now, if I do not hit it the right distance, I cannot blame anyone but myself.
Callaway 200 Rangefinder Recommendation Rating: 4
1: Something worth checking out if you have time
2: Something that is a hit for some people, but not a must for everyone
3: Something worth prioritizing if interested
4: Something worth making time to check out
5: An absolute home run, worth going out of your way for