Would you frame a house with a sledge hammer or tack hammer? Does a drywaller use the same taping/mudding knife on each coat of drywall mud? I would venture to say that the answers to the previous questions is a resounding 'no'. So, why would you use same tool to spray the outside of a house and to paint doors/trim work? Paint sprayers are designed to meet specific roles and uses. Let us examine the two most common paint sprayers in the residential painting market - airless paint sprayers and HVLP paint sprayers.
The popular airless paint sprayer is a very versatile and useful tool but can have it's limitations. These sprayers vary in size but most residential painters have one that can handle around .25 GPM(gallons per minute) and can generate up to 3000 PSI of pressure. These sprayers need this pressure to spray thicker materials like latex, elastomeric, and other modern day paints. The airless sprayers can lay down a lot of paint quickly in a production setting. The airless prayer can siphon from a 1 gallon or 5 gallon bucket with 50'-100' of hose that can get you where you need to be. The tips on the spray gun can be replaced to match the material and fan width desired for proper product application. The downside is that they generate a lot of material pressure(even with the PSI turned down) which means it isn't as suitable in the effort to reduce overspray and product usage.
The other paint sprayer is the HVLP(4, 5, & 6 stage turbine). This machine is designed for a finer finish in those delicate applications. Typically, the material will need to be thinned a small percentage in order for the HVLP to apply it properly. The HVLP is more than likely a cup gun or gravity fed system which would hold from 16-32 ounces of product to be applied. The transfer rate of material from the gun to the surface is around 85-90% which translates into less overspray and less product used. This machine can be cleaned out quicker than an airless paint sprayer.
So, in my humble opinion, it would be wise to have both tools in your war chest if you are a professional painter that likes to apply fine finishes to certain types of cabinets, trim, or detail work.