We were in Iceland because of a mechanics strike and had to spend a day and night near the airport. I wanted to do that anyway, so were positive about the experience.We booked a golden circle tour with RE because they would pick us up out at Keflavik. The tour itself was great. Our tour guide was knowledgable and we saw some neat stuff. However, the geyser stop is a pretty minimal attraction. Once you've been to Yellowstone or the thermal areas on New Zealand, this place was worth about 15 minutes. We were given a lot of time here to eat and shop.
Our big problem was in not understanding how their pickup and return service worked - was never explained. They did pick us up at Keflavik and then took us to downtown Reykjavik to a terminal where all kinds of buses came and went. We got on our tour bus easily and spent a pleasant day.
On the return to Reykjavik, they dropped off most all the tourists at their hotels in and around Reykjavik. They dumped us back at their terminal. We asked how we were supposed to get back to Keflavik and they looked at us like we weren't their problem. Finally, one person took pity on us and told us a bus would be going out to Keflavik in an hour and gave us a ticket for the six of us. So we cooled our heels in their waiting room with its plastic chairs and waited.
Before you book, get an explanation on your pickup and how you'll get home at the end.