Initial review of 3dPrinterCzar Prusa i3 kit with kids

I dont think it makes any difference, 2.5*60 was just the setting recommended to use on the You Tube cal vid I was watching, I guess its the same as typing in 150 like you say.
When you say "it jibbed out", what do you mean? did one of the m5 nuts come out of the x Axis holder? if so then see my fix in the photos earlier. I'm new to this printer too, so any advice is a help! :-). Just printing off a desktop holder for my Galaxy S4 at the moment to test the printer settings. I have found that PLA glue and water is perfect for getting that first layer of plastic to adhere to the glass bed.

it's hard to describe so i posted a vid onto youtube

[www.youtube.com]

its definitely not enough torque
T=I*a
I is a constant and because the steps/mm goes up a higher acceleration is required for the same value of mm/min
so im gona see about setting it to it's highest current (accurately with a multimeter) and see how fast it can go

The #defined constants make no difference how you enter them. The calculation is there simply to allow you to think in mm/sec instead of mm/minute.
For stepper motors, torque and rpm is correlated, and is typically published with the specs for the stepper motor. It does look like to me from your video you have found a point on that curve experimentally..