Seems that 1/48 scale is very popular (also 1/72) for WWI plane modelers, but 1/32 is coming on strong. Wingnuts and Rodin seem to be thw most accurate and most detailed 1/32 models available. The WNW models are now considered the gold standard. I am building the Junkers J1, and have the other three that they have on the market.
New ones are coming out mid-March. Shippong from NZ is free (for now) - included in the price.
Two websites to look at are:
Let's pichk this up on the aeroscale thread
My build is at