RE: Corona Receivers...
Corona receivers are pretty damned good -- possibly the best value on the market today in the 6-8ch DC FM area.
However, there are Corona receivers and their are Corona receivers.
These things are being sold under a number of different brandnames and choosing the right brand can make the difference betwen happiness and disappointment.
I buy mine from LightFlightRC and have been absolutely blown-away with the level of service they offer.
Others have bought elsewhere and received varying levels of support.
A few have bought from Chinese suppliers and found themselves out of pocket when/if something goes wrong (remember that nothing's perfect).
Do a search here for "LightflightRC" and "Vampower" to see just a couple of the better options.