I have a primos diaphragm that I have been practicing on in my truck to a cd. I think I have gotten pretty good with it.
Record yourself outdoors, from 10 ft away, and then re-play it. You don't sound like you think you sound. Not saying you sound bad, but our ears don't hear sounds out of our mouth like a turkey hears it, especially not in a truck.
You're better off being able to make 2 clear, repeatable turkey noises with that mouth call, and doing the right thing when you find a turkey, than you are carrying around 9 different calls and not being proficient with them.
Would yall say a diaphragm is easier than a slate or box
It's easier to shoot a turkey with both hands on your gun.