The Scenario: We're developing this new app which uses a selection slider to select some value (in this case, weight). Now, coming dev time, the client wants this slider to have an inertia scroll (meaning you can send the slide knob left or right on a touch+swipe event), while we suggest a "Touch & Drag" approach with accurate numbers and ranges, plus a manaul input if needed.
I've based this on a personal taste (I hate inertia scroll), but we have a Psychologist in our team and she also told us that an user weight may be a sensitive issue, so displaying values OVER their current weight (which will happen many times in inertia scrolling) might be very detrimental for the user experience. And more important, it will probably affect conversions since this element is a paramount part of the signup process.
However, our client tells us that they have tested this and people likes it better because it's "fun".
There are many reasons that lead me to the believe they didn't test anything and they're basing this on personal tastes. However, I didn't test this myself, so it's as personal taste as theirs.
Thus, I'd like to know: are there any studies comparing Inertia Motion and Value Selection on form data selection? I did a Google search and couldn't find anything, so this is my last resource.
EDIT: to further explain the concept, I'm including 2 simple images illustrating both scenarios