I use mine with my 9x running ER9x software. The short answer is yes, it's worth doing. The sticks are much better and you can program in things like expo and dual rates which helps. Sometimes it doesn't bind on the first try.
I have the stock TX too and do end up flying with that if I take the heli with me somewhere or let children fly it. The stock TX fits in the box it came with and its just convenient. Might be worth it to get the TX anyway, it's cheap!
One other thing, the stock TX doesn't seem to hold trim values when it's turned off. Your 9x will and that's nice.
It's a surprisingly durable little heli. Good trainer.
The USB charger seems to work at about 2C which is probably safe. The batteries are cheap so 5 or 6 batteries and a parallel charging board would allow you to fly pretty much continuously. You'll have to find the right male connectors.
Well I pushed the Buy it button on the V911-1 RTF + a pack of 5 extra batterys ...
Later I shall likely buy another 9x as I want more flexibility and I like the idea of Tx's ... using more than one in my mind is better security in terms of not over-drawing Tx batterys / capability etc. It will also allow me to run 1 Tx with original FlySky module while my existing 2 remain on FrSky. Either that or go for a CT6B ...
Because I want to use my FlySky system for the 911 when it comes ... I'm torn between whether to get another 9x radio (Turnigy without module - I have module etc. at home unused) or a 9xr and use that module.
Price is about same $50 ... but the 9xr is modified I believe for the LiPo tx pack they do at HK ... and HK are in trouble with shipping people for LiPo transportation.
So what to do ... I don't want to revert my FrSky 9x's to FlySky (I have two 9x now) ... and they are full memory's anyway ...
9xr or 9x ? To be honest because I know how to fit AA NiMH without any trouble to the 9x ... I am not convinced to choose 9xr just for that .. and anyway - the designed pack for it will cause trouble shipping.