Digital servos and analogue ones run with any TX and RX.
Digital servos respond a bit faster and perform at their maximum from the slightest movement.
Analogues need to turn a few degrees until they put out there maximum power.It's like a curved power delivery when the digitals are level...always at maximum.
I hope you know what i mean.
Digitals also drain batteries a bit faster than analogue.
At AU$39 i say go with the 945.