Everything I've seen brought the conclusion of: Buy the factory parts and save the head ache later when the aftermarket parts make your lights go haywire. ...
very close....but no cigar.
'03-'04 models can use the aftermarket self powered plug & play kits ($35-$45) or the Honda plug & play kit that costs about $100.
'05 & '06 should prolly use the Honda kit, unless someone who knows what they are doing installs a
self powered converter kit.
link w/ details (no plug & play available.)
'07 and up there is an aftermarket plug & play self powered kit (or 2) that seem to work fine, but I don't think they are especially inexpensive anyway.
In all cases a generic splice in type instalation should be avoided.
In many cases (especially '05 and newer) the Honda recomendation is probablly the best. In cases where a generic converter is used it is recomended that it be a self powered unit. (
link w/ details)
Some people have had good luck with a simple wire tap when used with LED lights (very low current draw) on the trailer. This works best in cases when the E is only tows that specific trailer, as hooking it up to a buddy's loaner or a rental trailer is likely to cause problems.
I've been following the trailer wire saga since doing mine in '04. I'm not especially up to date on the '07 up situation. Those cars have painted panels and are evil anyway. ;-)
Most of the problems in the early cars were related to simple spliced in wire taps, especially by places like U-Haul. Some U-Haul places did a quality install with a proper converter box, but not all. Some of the early converter boxes went bad (U-Haul, Draw-Tite, Hoppy, other brands, and yes, Honda too! ) and caused weird tail light issues, but a simple converter box replacement solved the problem. It didn't cause any damage.
In many cases, a standard (
non powered) converter was installed (as was the case for many '05 & '06 owners) and problems were encountered due to the vehicle's wiring not being up to the task of handling the extra current draw from the trailer lights. The "what-ever" brand converter or installer got blamed for the problem, when it was really just the wrong product for the application. However, I seem to remember at least a few members installing
powered converter units with good results.
Yes, its all here somewhere, but like you say Spam16v, it is all broken up and confusing....especially the relevence of a statement to a particular model year.
Good luck w/ your search!
Will