We booked the Blue Lagoon and Golden Circle tours with RE in June 2014 and were pleased. The buses were new, clean, and comfortable. Also equipped with free WiFi, though it could be spotty at times. Our Golden Circle guide was knowledgeable and friendly, with excellent English (BL excursion is not guided; they just take you and bring you back).
Both tours left on time from our hotel and dropped us back off within a couple of blocks. Note that for guests staying in the center of town, you will likely be picked up by a minibus, driven to the small BSI bus terminal, and from there be directed to board the larger excursion bus. The narrow streets in central Reykjavik simply don't accommodate the large buses.
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