It's definitely true that you get what you pay for. But as a noob, it's often difficult to recognize or understand what you sacrifice with a bottom-end model. So let's take a look at one of the least expensive 1/10-scale hobby-grade RC trucks available, the ECX Amp, and analyze the pros and cons of pinching pennies.
Analyzing the Amp
The Amp is a 2-wheel-drive truck that comes pre-built or as a kit. Both versions are priced at $130 and include a radio, battery, and charger. You only need to add 4 AA batteries for the transmitter. The kit version also requires paint for the clear plastic body. Obviously, the pre-built version will get you on the road sooner. But the kit version will jump start your knowledge of how RC cars work. Learn now or learn later. The choice is yours.
I highly recommend choosing a 1/10-scale model for your first RC car. They are large enough that the components are easy to work on. At the same time, these cars and trucks are not so large that replacement parts and hop-ups are prohibitively expensive.
Like most modern off-road models, the Amp has a molded plastic chassis, long suspension arms and oil-filled coil-over shocks. I've crashed the truck into a few immovable objects and it has proven to be tough.
The transmission has a gear-type differential. Many racing cars and trucks use limited-slip differentials. While limited-slip diffs allow tuning options, they are also more difficult to assemble and require maintenance. Gear differentials are very tough and work well in most situations. They're definitely the best bet for newcomers.