Associated just came out with the Pro4 SC10. It's $320 for brushless without the battery, so you might want to put that into consideration:
https://www.associatedelectrics.com/teamassociated/cars_and_trucks/Pro4SC10/RTR/specs/
I saw that already. The driveshafts look almost the same as the Senton. They are definitely the same style at least, and look to be made of plastic, but, if that is the only part that may eventually need to be upgraded, i might be able to live with that. I also have an opportunity to buy back my old SC10 belt drive 4X4 (i was on Associated's site looking through parts availability for the SC10 when i saw the new one), but I'm not sure i want to give that to a 9 year old, since that truck was set up for racing, and is in no way a basher. At least then my personal collection of discontinued vehicles would be complete. I already have an Arrma Fury and a Racers Edge Pro2/Team C TS2. The SC10 was my first 4X4 SCT race truck, when i was still racing. I have to remember though, I'm doing this for a 9 year old, not me LOL.
Arrma made the 1/10 4x4 vehicles to make that price point and it really shows once you actually start look at these things. Plastic balls in the rod ends? None replaceable rod ends on the shocks. Turnbuckles that bend or break like twigs. Crappy steering servos. The fixed motor mount is oftentimes made wrong causing the motor to bind, both of mine were made wrong btw. Tires that blow apart. A arms that are made from glass. Plastic driveshafts that twist themselves apart. Front c hubs and caster blocks that are made of glass. And let us not forget the stupid motor module design, that's supposed to be easy to remove but instead takes prying with 3 screwdrivers to remove and traps dirt inside of itself that just destroys the bearings in the slipper and motor. And now your $300 rc has just become a $400-500 rc because you have to fix/replace all of the crap they couldn't get right and you still have to deal with the stupid motor module.
As much as I like Arrma they really need to go back to the drawing board on the 1/10 platform.
A lot of these issues are why i ended up with my first DHK Hunter. I originally bought a V1 Granite, liked it at first, so then i bought a V1 Senton, but after a couple months of hard use, i had issues with driveshafts snapping, even after loosening the slipper, then had to replace the motor, then the servo, then the ESC twice, so then i put a mild BL set up in the Senton (3300KV motor, HW 60A ESC), and it seemed to just make the issues worse. Granted, both of them were Mega versions, but, it just seemed to be excessive, and then i kept getting told that to make it durable, it would be better to upgrade at least half of it to the BLX version, and even buying a complete BLX roller on eBay would have been another $200 plus per truck. At the price point the Mega is at, I'm not looking for bulletproof, but, when you start getting told that you need to upgrade some parts with Traxxas parts (originally, that was the only way to upgrade the plastic axles), since they are more durable, thats when i step back and rethink things. Even now i dont think Arrma makes a metal upgraded driveshaft, but, i also havent looked into it since i sold my Senton, and then gave my Granite to a 10 year old. I do have to replace parts in the rear diff, yet again, in the Granite, since one of the outputs is seized to the housing again, and its back to brushed and keeps doing that.