Techno-Isel Components

[CAMCRASH]

I am looking at incorporating Techno-Isel Components in a 3 axis gantry style router

does anyone have any experience with their rail & ball screw systems?
Is there any other recommended companys that would supply liniear components for router of the below specs at simmilar prices that I could investigate?

Current design plan is to have 48 x 48 x 12 work envelope
X axis -- w/ side mounted rails on top of the frame with dual lead screws
y axis -- w/ one top & one front mounted rail -- single lead screw
z axis -- w/ carriges mounted to the frame & rails mointed to the head
Frame to be built out of 80/20 AL extrusions 1.5" series

currently I am looking at ( Series I ) rails on all axises
Short carriage (4x) on X axis
Long carriage (2x) on Y & Z axis
16mm x 5 pitch pre machined ball screws
KM Series ( anti-backlash ) ball nuts

Do I need to worry about sag or wip on the 1500mm lead screws
Is there a formula I could use to calculate estimate screw wip & rotary speed
Also I plan on leaving the Z axis ball screw unsupported at its end
Is this a NO NO or will this be ok?

Motors I plan on using will be NEMA 34 w/ 1200 oz/in
I would like to get 300 IPM rapid & 75 - 100 IPM feeds

Any information / reccomondations would be greatly appreciated
As you can probably see this will be a first time design & build
So I am as green as the come and would hate to be heading in the wrong direction with my project

[dcms]

Did you ever get any response? I have similar questions.

Thanks