Some time ago, I received one of these, but I only recently got a chance to install it.

Installation was very straightforward; the instructions were clear, the parts were all there and they FIT!

The hardest part of the job was removing the three copper taillight contacts which are clipped into the plastic housing, but the Ecliptech kit has cleverly designed one of the parts to double as a removal tool, and the instructions warn that you may have to push a bit, but assure you that the contacts WILL come out without breaking the housing if you use the tool as shown. It worked fine.

Once the contacts were out, the pieces readily assemble into the taillight housing with the tattail hanging out the back. The instructions even tell you what to do if you overtighten (easily done, as very little torque is needed). I like that all the nuts are nylock, so no worries about anything rattling loose.

Once assembled, installation back on the bike is the work of only a few seconds. The rattail means the new light is even easier to clip to the harness than the original.

Now, just re-install the two OEM taillight screws, and you're done! I could have done this entire switch in less than 10 minutes, if I hadn't been taking pictures. One thing I did wrong--I managed to get the wires mixed up when clipping into the harness, it was entirely my fault (the instructions are clear, I just misread the wire colours) and then I compounded the problem by failing to check the brake lights before riding! A friend noticed my lack of brake lights, and it was a simple 2-minute fix in a parking lot after lunch...
I've gone from this:

To this:

Took maybe 10 minutes total working time, following the very clear instructions and using the included parts and tool (the only tools I needed to supply was a phillips screwdriver for the taillight lens screws--I used the one in my bike toolkit--and a small wrench). The nylock nuts supplied with the kit are a VERY nice touch--and I like that all the nuts are the same size, so only one wrench is needed. The insert looks and feels tough and solid, and it is VERY bright. And the instructions even include some advice, such as using silicone to caulk the clear license plate lens on the bottom of the taillight housing (a good idea).
If you ride in traffic a lot, or are concerned about your visibility from the rear, this insert is a good idea. Comes in two configurations (mine is the standard--check the site). Supplied by our own Bueller from Down Under!