Somebody a few posts back asked about them, here is what I posted then. Hope it helps.
Hey, I just installed the sequential kit from webelectronics.com I bought them off their site. You may know they offer a kit for $179. which comes with a modified harness. You can send your orginal back and get a $40 refund. That means $139 but if you'll pay a few bucks to ship your harness back so assume $145 or so.
I bought the kit from them for $89. There was no shipping so just $89 total.
I had it in 2 days (He sent it Priority Mail)
This kit requires you to make a few connections.
I had it installed in 30 minutes. The instructions were so detailed since it was specifically for our car 2005 Mustang. There were no extra parts to buy. You just need some basic tools to snipe a wire , a socket wrench.
All the mods are behind a panel in the trunk. You cant see them. You basically take the black plastic cover off the inside of the trunk, reach in and unbolt the 3 nuts that hold your taillight in place. Slide out the light and remove the harness. It takes a few minutes to snip a couple wires and connect them with the leads form the module that the kit has. Then just reinstall. It seemed too easy so I went even slower thinking I was missing something and it only took a half hour or so.
I can't imagine anything really happening to ruin the vehicle or cause a service call. Unless you don't wrap a connection well and it grounds out. At that point you will just be replacing a fuse. I don't think a voided warranty would result. From what I notice on this site, there are a lot of idiot dealerships out there and pleanty of good ones too. You never can tell.
People always add to their vehicles. I guess ask yourself
If wiring a Trailer plug onto your vehicle/truck does not void a warranty, why should this???? If wiring Fog lights into your car, or wiring a new stereo or speakers...why should this?
The way I see it, I saved about $55 bucks and had it done in less then an hour. I also did the mod myself which is kind of a cool thing when somebody asked...you can at least feel good that you did some actual wiring and got your hands a tad dirty
That $55 will go towards louvers or some other mod now. $55 plus the satisfaction of tackling a project means more to me than to others. If you have the means...($$$$$$$)or are uncomfortable with basic wiring then by all means....go the easy route and get the completed harness.
I am totally satisified with their product