I am planning to build a steady rest and found this plan that I am thinking of using. Any pros/cons to using t-track instead of slotted plywood?

http://woodarchivist.com/3302-diy-lathe-steady-rest/

Also identified these wheels which I can buy one at a time. Thoughts on these?

https://www.amazon.com/gp/product/B0...XH3E97F2&psc=1

Interested in other's experience before I order some parts and get started.

Thanks.