I am looking at picking up an Explorer I and love the new 40mm dial and watch but I know everyone says the 36mm is a classic and correct size for most people. I think my wrist can probably support either of them, as it is a bit under 7 inches, but I am 6ft tall, so everyone at the boutique said the 40mm looks better on me even though the 36mm still looks very good on my wrist I think. Getting older though, it's also nicer to have a bigger dial to see everything more easily
Would love to get opinions though and will try to post pics of each too...