You'd be surprised, there is NOT a big demand for this kit.
Because you are selling it in the wrong store. Sell it via Sparkfun and Ladyada and you will see demand, no one knows about your store.
Only the 15,000+ people who read the silicon chip article, probably more again who read the recent EPE article, and another 10,000+ of my own viewers...
I don't know if there is enough margin in the kit to sell it via a third party channel.
Dave.
About Sparkfun: I once tried to sell one of my designs on their site. They actually evaluated it extensively. Dave, I sent you an email about it a few months ago. It was a PICAXE controller. It looked like a relay control board on steroids, with opto-isolated inputs, PS/2 port for a keyboard, a breadboard area, an RTC and EEPROM, some analog inputs and the list goes on. One of the reasons it called their attention was the documentation. I did a block by block explanation mentioning every component and it's function. It took me like 3 days to get it right. Dave is very good at that. Unfortunately they rejected it because they though there was no market for it.
Do a brief description so beginners can understand the uCurrent. I think there's a good market for it. If you use microcontrollers then you use the uA range frequently.
I don't see any reason for one of these retailers not to make a deal with you. Sparkfun actually produces their own boards, but Dave uses very specific components I'm certain they won't have in their inventory. Maybe you can send the reels or the finished product.
Sparkfun is very friendly, I have to admit. Now I am collaborating in an english to spanish translation of one of an Arduino "Introduction to physical computing", if my memory serves well. I'm in charge of proof reading and checking the grammar and coherency of the text. It is an open source project, so I get not money, what I do get is attribution. At this stage this is more important for me.
Sorry for sounding like a Sparkfun advertisement or a personal story. I just want to point out this guys can really take you in consideration.
Ivan