Found this on Arnies:
http://www.arniesairsoft.co.uk/f ... pic=140844&st=0
"This mid 2008 celcius will be releasing the CTW M4A1 - Advanced System. Mede in Hong Kong, this high fps aeg is designed for military training. Size and detail matches the real M4. Marui type aeg's have thicker bodies to accommodate the gearbox. CTW gearbox is thinner and matches the size of a real M4, with parts compatible with a Systema PTW.
For airsoft players, dont need to worry, because celcius will be providing a Civillian version with 350-550 fps using 0,20 bb's. just by changing the cylinder, users can change their fps in less than 10 seconds. So for safe gaming it can be adjusted to each clubs rule."
Pictures can be found in the post.... especially what you can see of the gearbox...
The original post mentions retail to be under $500.....