Burke comparison needed.

Hello all,
I have a friend who is interested in purchasing a Burke Low D and wants more information. So, I figured I could ask all you dear people for some input. :stuck_out_tongue: Could anyone give a comparison of the hole placement on an EZ model, a Viper, and some other brand of whistle? (A Dixon Polymer would be ideal.) Also, does the smaller hole spacing on the EZ effect the tone dramatically?
Cheers,