If you strictly into 1:200 then for the following a/c I recommend:
747: Hogan and Skymarks/Risesoon
787: Phoenix and Hogan
777: Hogan and Skymarks/Risesoon
A330/A340: Hogan
For the smaller a/c i.e. A318/319/320/321 and 737's there is Gemini and Hogan.
Herpa while using the Hogan moulds, makes some interesting subjects but is alot more expensive i.e. the Hogan Qantas A380 is available for less than $40 whereas the Herpa version is close to $100 and they're basically one and the same thing.
As for retailers, I've bought alot of my stuff from JPF and Diecast Airplane but I'm getting alot of models from
Jetway Models, Gemini Jets, Dragon Wings, AeroClassics, Herpa Wings, Starjets, Jet-X as the prices are more than reasonable and the service is great.