Yeah - forgot to state which colour I wanted when I ordered!
David, I've had a practice 'dry run' with the grip so far, but not used it 'live' yet.
It certainly seems to make a difference, bearing in mind that my problem, due to Rheumatoid Arthritis, is not only holding an airbrush the 'traditional' way, like a pen, but being able to operate the trigger as well.
Because my index finger, and second finger, lack articulation, and are both extended (that is, bent up and back the wrong way!), I have difficulty with precise control over the trigger, whilst holding the brush sufficiently secure for accurate spraying. What's worse, with the 'brush shown in the photo, the top-mounted cup gets in the way of the stiff fingers in 'normal' use - my previous 'brush, although almost identical, had a side-mounted cup, out of the way of the fingers.
This, coupled with the lack of grip, caused severe stress on the wrist and, as a result, the upper arm muscles, tendons and nerves, as well as severe discomfort and some pain.
The pistol grip seems to relieve most of this and, although it's still difficult for me to operate the 'brush's top-mounted trigger with absolute precision, it is certainly a lot easier, and nowhere near as uncomfortable or painful.
I would think that the average able-bodied user would find the pistol grip very useful, especially on large or more time-consuming spray work, although I've yet to discover how the physical presence and size of the grip, small though it is, will effect handling during delicate, close tolerance work, such as fine lines or mottles, for example, if there is any effect, of course.
Once I've had a chance to use it 'for real', I'll post a summary report.