RE: The NexSTAR arf cost more to outfit than the RTF
When I see my Nexstar ARF next to the Tower Trainer (or most other trainers for that matter) on the ground AND in the sky, I'm very happy that I got the Nexstar. All of the add-ons that come with the ARF do their job very well; they make your first few flights slower and easier so you have more time to react to things like wind or dumb thumbs. They come off very easily, and the plane flies faster and is more maneuverable.
The Tower Trainer does work well, and does last a long time, and is $25 less. To me, the looks, the bolt-on wing instead of rubber bands, the bolt-on tail, AND THE EASIER ASSEMBLY (no gluing =) all make it worth the few extra dollars. It is built like a rock and will last a long time, too.
Either way, like was said above the ARF is not more expensive than the RTF. The equipment above is better than what comes with the RTF, and the total price is less.