Hi everyone. I’ve been using Netduino Plus for developing for some time. The problem is that it only give 32KB of RAM and 64KB for flashing my programs.
So I need a bigger development environment, and I had thought in FEZ Cobra. Now I’m studying some other alternatives, but I think, FEZ Cobra will be the future.
Cheers 
Welcome to the community. I also suggest you peek at our smaller FEZes, like FEZ Panda. Even though they have similar “shape” to your device, they are more capable and have more memory, thanks to GHI’s libraries. FEZ Panda Support Ethernet through a native driver for external Ethernet chip so no memory will be wasted on Ethernet stuff. You can read more about this here under “USBizi network support” GHI Electronics – Where Hardware Meets Software
Also, take a look here http://www.ghielectronics.com/catalog/compare/
I suggest you explain what you want to do then us+community can give some suggestions.
The app I’m developing uses an HTTP Server, an HTTP Client (that sends and receive SOAP messages) and some other code reading and processing some ZigBee frames from one UART.
The final assembly is about 200KB, but inside there are some of the Netduino+ libraries so, this should be smaller (only a few more).
As I need Ethernet support, I have to buy a FEZ and the Ethernet shield, total price of this two thing is near to the FEZ Cobra one (which doesn’t need Ethernet shield, and is more powerful).