I've personally never ordered from Banggood or Aliexpress, but I have ordered a lot from HobbyKing. They are still one of the best sources (in my opinion) for cheap lipo batteries and decent cheap servos.
I agree with
@kdobson83 and I try to support local hobby shops and retailers based on in the same country as I live. To that end, I like to buy my FrSky gear from Aloft Hobbies (California), I've also ordered some Cobra Motors stuff from Innov8tive Designs (east coast) and I've bought a few things from Flite Test/Amain.
As much as I like to be 'loyal' to a shop, if the shop doesn't carry what I want, time to find a place that does. I spread my money around.
You can also try keeping an eye on classified ads both here and over at RCGroups forum, you might be able to find a good deal or two on some used or near-new electronics that fit your needs.