The TRX4 is a fantastic rig right out of the box. It’s the easy button for a ready to run crawler-ish RC. Two speed transfer case, front and rear lockers, traxxas reliability. It’s not the sexiest rig, and there aren’t a ton of hop-ups for it, but it doesn’t really need hopping up other than sticky tires. In the RC world, it’s an entry-level cheater rig. Off the shelf it’s better than a lot of hand built expensive trucks.
If you want to immerse yourself in the RC hobby, building cars, agonizing over which motors, links, shocks and gearing to buy, the trx4 isn’t it. RC4WD and Boom Racing are the rigs for experienced tinkerers.
I’m speaking mostly of 10th scale trucks. No real experience here with 24th scale. Nathan does have a 24, but I don’t know much about it other than it’s a lot cheaper to build and run than the 10th scale stuff.