3 SPADs is an ambitious endeavor and these are already looking good! I tend to build in pairs, although I've occasionally built 3 or 4 WWII types in parallel. I agree with smperry, it does seem more efficient. Sometimes I almost dread the more tedious tasks like pin washing panel lines on three or four models; I usually end up feeling like Jack Nicholson sitting at a typewriter. I once built an H-75, a Fiat G.50, and a Bf 109G-2 that were all in the same Finnish livery and by the time I was 2/3rd finished with all of the masking I was about ready to just dip the last one into a bucket or black paint and call it recognition model. Discipline and patience, I suppose.
This will be a fun project to watch, RAGIII, and I'll be paying close attention to learn all I can from your build.