Here is one example I found:

It appears the TS-70 (Tower Brand) = CS-70 (Hobbico Brand) = HS-645MG (Hitec Brand). The specs are identical for all of these servos, and the replacement gears listed for the Tower and Hobbico servos are the HS-645MG replacement gears.

I bought a set of TS-70s for my Twist 150, and they have worked flawlessly so far.

I look for identical specs, identical case shapes, and replacement gears, if they all match up, then the Tower or Hobbico part is probably a rebadged name brand.