anyone use one of these? I have a motodynamic  on my s2r,  but am looking for one to use on a project bike and wonder how they compare..

http://www.kapscomoto.com/product_p/itl-d99.htm

i bought one and it's fine.  no instructions so you have to poke a bit with the wires to figure out which is which and there is only one ground, but it's a good replacement for the original.  visibility is decent.

Yeah, for $30 i'd say it's worth a shot. Hell a stock red tail lens from Ducati is $20...

Does what it is supposed to do and has held up to the vibrations of the bike so far.

The plugs it ships with don't match with the wiring harness, so you'll have figure that out.

I took a trip to radio shack and bought $5 in parts to prevent hacking up the OEM wiring harness, but I'm sure soldering would work fine.

I have one and its been great. Kapsco has a bricks and mortar store just outside Toronto. His budget bar-end mirrors are also OK.
Cheers
Mark

Update on the KapscoMoto Tailight after a year:
I noticed something rattling from the rear of my bike. Isolated it to the LED taillight.
I thought maybe the cover snapped in or something as there were no screws securing it to the base, with a slight tug it came off. It does not snap it, it is glued.
Both ceramic resistor covers (heatsinks?) had somehow released themselves from the giant resistors and were rattling around inside the cover. Put them back on with some high temp adhesive and reattached the cover with superglue.
All that has apparently fixed the problem.