Ok, here's the thing, it all depends on what you want to do, what kinds of aircraft you want to fly, and so on.

A basic 6 channel has all the features most guys ever use.

However, most 6 channels don't have a large number of model memory slots, so you wind up buying more TX's or having fewer planes.

HOWEVER, if, by chance, you do progress in to models that require more channels, you'll outgrow that 6channel box pretty quickly. (but, like I said, the vast majority of guys out there never use the fancy features available on the more expensive radios).

So, buying a radio is almost crystal ball gazing. If you just KNOW that you want a scale turbine warbird with all kinds of functional gadagets and so forth, then that 6 channel box isn't going to cut it. If you want to try flying competition acrobatics, that 6 channel box will likely disappoint you. But if you just want to fly a variety of sport and stand-off-scale planes, that should be ok.

One thing is sure, you aren't going to wear out the TX. (the batteries, maybe, but not the TX).

So, get whatever you can comfortably afford. If you buy more radio now, you don't have to buy it later in the unlikely event that you need more TX functions than you have now. But you can always buy whatever you want later, and sell your existing TX to someone else, or keep it as a knock-around or buddy box (if you get in to doing instruction, it's handy to have a buddy box of your own). And if you buy later, in the end, you'll pay less and get more features when you finally are ready to use them. Radios are getting more features at lower prices all the time. (and, my crystal ball tells me that it won't be long before crystals are a thing of the past, and all radios will be totally synth on TX and RX end, and number of model memories will go up even more. So anything you buy now will eventually be "outdated". "outdated" but perfectly functional.)

How's that for a non-answer.