honestly, if racing is even remotely on your radar, id avoid rtrs almost entirely. the only classes you will be allowed to run those cars in would be modified. depending on your driving skills that could turn you off racing entirely.
rtrs are all gonna be plastic cars with too much horsepower lol.
id avoid the tc4 unless you wanna race 17.5 or slower turn classes. it CAN be raced in modified but you will likely be replacing a lot of stuff and who knows how much longer the car will be supported. also it doesn't have the optimized suspension you would get with a newer car.
electronics don't have to cost a mint. i put a $350 car together to race 17.5 just to see what you get. raced it directly with $1000 cars and it worked just fine. id still look to get into a used racing chassis from 2011 or newer though.
you really would be surprised what you can get around $400 in the classifieds. id be surprised if you couldnt get a roller with electrics. just drop in receiver. you would be much happier with that i think. just add a $60-$100 spectrum.
I will say, if you wanna race; go to the track you wanna race and talk to people. if you are really set on an rtr, you need to find out what they will let you run on their track in competition. some clubs are more anal about rules than others.