Hi!
I recently designed a AR Envelope Generator for modular synthesizers which I want to provide kits for people who don’t want to etch their own pcbs or build it on strip boards. A friend told me about your site and your price is surely the lowest I’ve seen on the web. Since your prices are for 2 layer pcbs I’m even thinking about redoing the layout for a pcb where you can also put potentiometers, LEDs and jacks onto the board for easier assembling.
Ok but anyway, here’s my question: I’m working with open source software KiCad and when I ask it for a drill file it gives me a file which ends with *.drl, is that ok for you? Do you have any experience with KiCad Gerber files? And how is this thing running with the free kit? 
If this works out nicely, I have a lot of ideas for future open source projects.
Check out my stuff here: http://zaunerelektronik.net, I’m talking about the Zauner Quad AR Generator.
Thanks for you answer!