I was looking into the Spektrum transmitters and receiver which might not be a bad idea to get

As for the servo's does it have to be titanium gear ones? I've looked at just the metal gear versions and most have over 150oz of torque instead of say 300 like the titanium counterparts. Also I've seen people with separate Bec's which I wouldn't like to get. The esc can provide enough power to servo can it not?

For motors/esc a combo package from the same company may make it easier and dependable I think. I'm not racing but I have a MM already so Tekin might not be a bad idea for something different. Tekin motor says the size is 71 mm and the max that it says for the Losi chassis is 70mm.