I usually shoot with a couple of D810s, to which I've added MB-D12 battery packs as I've got big hands and I'm used to larger camera bodies, and they also have the advantage of 6fps and buttons designed for the vertical orientation. The D810's resolution and sharpness are just astonishing. I found myself making extra efforts to keep my elbows tucked right in so I'd look less like a photographer when I'm using it, because you can see me taking the picture in the reflection in the eyes of the person I'm photographing – the quality is that good. For such a high resolution camera, the ISO performance is excellent. I'm fairly noise-phobic, so I don't usually go past ISO 6400 on it for high quality magazine work, and at that level it is quite incredible. It's an amazingly robust camera, too.
I recently borrowed the new D5 to use on a job photographing for a speed-skating academy in Germany, followed by ice hockey in Slovenia, and I also took it to Myanmar on my last workshop. It's a brilliant camera. Having 12fps is amazing, as is its low-light performance; on the trip I got really used to having a good two to three stops more than I would with the D810, so I'd be comfortable using ISO 25,000 to 50,000 for a shot I'd be planning to blow up and use as a spread in a glossy magazine. What's also good is the D5's sharpness; the self-calibrating AF seems to have made a huge difference with the 80-400mm; and it can do this on the fly, fine-tuning automatically as you're shooting. I'd love to have one in my camera bag the whole time, but I'd probably only use it for 5% of my shots – the D810s are what I need for daily use. But I'm open to offers!
What I do find amazing is the changes that DSLRs have gone through in the 12 years since the D2X was released, from 12.4MP and a maximum ISO 800 to the 36MP of the D810 and native ISO of 102,400 on the D5. It certainly gives you more opportunities. In Myanmar last November, I was shooting the Taunggyi fire balloon festival with the D5, when a box of fireworks accidentally dropped from an ascending balloon caused a huge explosion. I caught the whole thing on the D5 and the shots got picked up by The Sun. So as well as being a travel photographer, I'm now a roving, slightly raving, news agency!