55w has a greater intensity which can change the color of certain temps (e.g. 4150K can be as bright as 5000K 35w). I personally have a 5000K 35w which provides sufficient light for what I need.
OEM retrofits change the projector to a HID projector which also means you (may) have to change the bulbs to D2S or the stock D3s which come with the Edge's HIDs.
Previous Edge: 2008 Edge SE
Current Edge: 2011 Limited
I know that mine is a drastic step up but the differences are as follows:
a) The 2011 is wider than the 2008 which leads to a more comfy cabin
The 2011 does handle better
c) The 2008's trans seemed to perform better
d) The 2011 is smoother and quieter
e) The 2011 has a more refined look that gets compliments every time I drive it
f) Both have good customization potential but need some tweaks performance wise
If you have DRLs, you will need a couple of other components to go with the original kit.
a) DRL Module
Warning Canceller
Also, bear in mind, I used a totally different vendor than everyone else.
I am running a 35w 5000K kit I bought from a vendor on a Maxima forum I moderate. It's been pretty stable, even when I had the DRLs running. However, I am running Canbus ballasts.
Another option I may have is to get with a friend of mine and do the refinishing of the cladding. I would also need to speak with a paint shop in Mesa for the supplies.