Give it a good run around the yard for a bit, you'll notice certain parts of its range the receiver won't respond or the signal seems laggy. I have a 3pk with the spektrum module/receivers. I tried all 3 of the receivers I bought, all did the same thing. Throttle response was laggy at times then it would loose signal all together on steering and throttle.
I contacted them and was told to send everything back in for an update. It's ok though, once the kinks are worked out this setup will be perfect!