If you ask my opinion, you need to consider more than just the # of leds on the drl. You should consider the dimensions, where you are putting them, their specs, the price and the look you are trying to achieve. Since I've not seen any after market drl's that are a direct fit for the ex, you have to settle for more of a generic drl. If you look at my ex above, those are a 5 led design with a 15 degree rake to them (this matches the curve of the bumper so the drl beam is pointing forward), yet they are 8 inches across and a little over an inch wide and are rated at 1W per led. Philips has a 4 and 8 led module but are quite small in dimension which would work for an in grill solution. If I wanted to spend the $, I would have bought the real hella version instead of a knock off. they look about the same and are about the same size, but are rated at 5W per led, which would equate to a much brighter drl. Mine are really bright but the real hella would probably match the intensity of what you see on a Mercedes or an Audi. Cheap drl's can be small and easy to install but do not give off enough light in sunlight to be a good drl solution. Here's a link to the real hella.
http://www.myhellalights.com/index.php/default/daytime-running-lights/universal-daytime-running-lights/
Mounting and placement consideration will come into play. You can fit a small drl in the grill. A larger drl, such as the ones I used, are not so easy to mount. depth comes into play also. I ended up having to fab brackets and cut holes in my bumper valence to achieve the look I was after.
Here are some other threads about drls. I think you will find them useful in your quest to find a drl look for you.
http://www.explorerforum.com/forums/showthread.php?t=391952
http://www.explorerforum.com/forums/showthread.php?t=322848
http://www.explorerforum.com/forums/showthread.php?t=326130
http://www.explorerforum.com/forums/showthread.php?t=324605