On every modern rc system even cheap chinese receivers that cost around 10 USD the PPM decoding is done with atmel as far a I know.
In most of the cheap RC toys in the UK atmel chips are NOT used. Google "TX-2B" and "RX-2B" this is (I think) the most common coder/decode used in cheap chinese rc toys shiped to the UK.
Using just an Uno you could deal with 64 channel "digital" RC.
Do read DuaneB's blog on RC model hacking and look at his code for reading PPM signals. Both are most excellent!.
Where I live buying only the atmega will cost as this whole board or more
Where on Earth do live do live!
Mark