The dive at Silfra was one of the most amazing things I've ever seen. As a geologist, diving between two continental plates is about as awesome as life gets. But I was really surprised by the serene beauty of the fissure. We were lucky enough to have "full" sunlight (I mean... it's still Iceland... but there were no clouds) while we were down there, and the rainbows could be seen on rocks about 30m down, which was brilliant. The water was so clear, and honestly, the best tasting water I've ever had. We drove past there the next day just to fill up our water bottles.
I'm not an experienced diver, I had only just got my Padi open water qualification before arriving in Iceland, and had never experienced a drysuit before. Our guides, AJ and Chris, were supremeley awesome in helping us gear up and explaining the ins and outs of a drysuit. When in the water, AJ was very patient and helpful with our groups' novice-ness. As warned, our first dive was really just getting used to diving and drysuits. The second dive (after a much appreciated hot chocolate) was where we were really able to soak the dreamlike quality of Silfra in.
The drysuits were quite cumbersome and uncomfortable (particularly around the neck), but that's kind of the whole point, and you don't notice it all when you're in the water... though you probably would notice it in the water if the seals weren't so tight. So it evens out.
The walk back to the van was the only bad part of the day, but it's really not THAT long, and if you take ages to do it, the guys will drop their stuff at the van and come back and help you out (thanks AJ!). It's not even close to being a reason not to do the dive.
Dive.is were really great to deal with. They were understanding that drysuits were not really a thing in Australia, and accommodated us. They picked us up from the house we were staying at (not a hotel, but not a problem for dive.is), and dropped us off afterwards.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.