I have the DX5C and its a fine radio, but I only bought it to bind all of my Losi/ARRMA vehicles to a single radio. There are several radios in the same price range or much cheaper that are arguably better. Personally, I haven't had the best luck with Spektrum since I started buying their stuff in 2008. I've also heard the Smart Phone app for the DX3 is absolute trash, but I don't have any personal experience with it. Regarding their batteries, servos, etc, the same thing is true. There is better stuff for less money. However, if you're very new to RC and haven't yet learned about the ins and outs of things like LiPO charging/safety, then their charging ecosystem can be a good band-aid.

I'm interested in your TT-02 stock build. This sounds like a racing spec class? The normally included Hobbywing 1060 ESC is fantastic for brushed racing. Also, does the 2-in-1 receiver bind to DSMR radios like the DX6C?