Don't change simply for the sake of change. If you don't need or want more channels or features, keep your money in your pocket. Some people buy a new, inexpensive, 4 or 6 channel system for each plane. Others want a single transmitter to control multiple planes. That's where computer radios typically have the advantage. You have multiple model memories to store the setup for each plane. With a 'standard' transmitter and multiple planes, you have to set servo reversing and trims every time you want to flya different model. Another advantage to many computerized transmitters: you can get the mechanical adjustments 'pretty close' and then use the transmitter to make very tiny final adjustments.

Also, computer radios allow for mixing channels together. Mix a little rudder with aileron for coordinated turns using only the aileron stick. Mix flaps and elevator eitherfor low speed hndling orto enhance aerobatics. Many possibilities depending on the radio and the plane.