I have long had a Fuji Q4 system and have been very pleased with it. I bought a wide range of nozzles, but have never used the largest (or the smallest, in fact) - I had intended to use that with emulsion, but I then bought a Graco Airless system that I only used for painting a few rooms - once you have masked up, the painting takes no time!. Subsequently I looked into converting the Graco airless kit to Air Assisted, but in the end bought a new Wagner AAA kit (Cobra 40-10 plus AAA gun) - this was extravagant but it is superb, although I am still at the learning stage of using this. I kept the Graco airless gun and have the option of using this with the Wagner pump in airless mode for room painting.
The thing is, and what I thought may be relevant to this thread debate, that I am undecided whether I want to keep the Fuji HVLP or not. For any larger sized job, the AAA is better, but for a small job, I find the Fuji to be simpler to set up (and clean). For the Fuji, I have 3M PPP cups that makes the system very nice to use and economical with a small quantity; the Wagner is fed from a 5 litre hopper which is economical compared to many airless kits and cleaning is likewise comparatively economical, but it still seems overkill to spray a chair, say.
Technically, the AAA kit will do everything, and probably better, but at the moment I am hanging on to the HVLP as well for the convenience factor.
Cheers