Question about Acceleration values

Setting up for controlling X-Carve CNC ~
I think I have most of the config worked out ~ except I am not so sure of the values for Plan Ahead ~ acceleration
On the CNC section (smoothieware.org) ~ you recommend turning down the acceleration ~ “Depending on your machine type, a good recommendation is 25mm/second^2.”

This is what I have done in the Config ~
acceleration 25 # Acceleration in mm/second/second. (Original Setting- 3000 <-my notation)
#z_acceleration 500 # Acceleration for Z only moves in mm/s^2, 0 uses acceleration which is the default. DO NOT SET ON A DELTA

is this correct ~ I am seeing a couple of forum posts where some have set Acceleration to something like 1500 ~ so I just want to be sure.
I include the disabled z-acceleration as I am wondering if I should enable and set that to some value or just let the first line set the acceleration.

Imported from wikidot

This sounds about right. Once everything works, you can try increasing it, until it starts causing problems.