Steve, Your 2.4 gHz HENG LONG Transmitter will absolutely play safe with other Tanks BUT because the RX18 control board and indeed the whole Tank is built down to a price you cannot hope to achieve the performance of an after market Control board and that is why many of us choose to upgrade to a more efficient and better equipped and capable control board which of course costs more,
If you are happy with your Heng Long Tank then you are in the company of thousands of fellow happy hobbyists,
All I am doing is pointing out that if you wish to improve your Tank the equipment is available, and there are a whole bunch of very able people here willing and able to help you make the changeover.
Shaun.