This thread still going huh.
As pointed out comparing the 2 different styles is pointless. But that said, the op asked the question so I will answer.
Direwolf20 for all the reasons mentioned in previous posts for me.
I used to watch Simon n Lewis but tbh I don't anymore.
It's not because they are getting stale, it's because I find they have changed from their early days.
There is an undertone now that they are somehow crucial to Minecraft and very important.
At least that's what I take away from their vids these days.
To me it seems like they equate the number of subscribers to some kind of real world currency that gives them some perceived ownership of "Minecraft".
You may not see it this way, as I said, that's what I take away from their vids these days.
In comparison, Direwolf20 plays with Devs modders and other well known youtubers. And as a result arguably has much more influence than the yogs, and yet he displays no arrogance or any sign of inflated ego.
Add to this I find his vids more rewarding, then for me it's an easy choice.