CNC X-Y Table: Linear Motion Cassette

I'm in the early stages of building a CNC X-Y Table - (probably 4' X
8') and am interested in hearing about others' experience using
linear motion cassettes (e.g. Thomson, Parker, SKF, THK, etc.) for
the Y axis. Please share any thoughts.

Also, the Torchmate II incorporates a linear motion cassette -
anyone recognize the manufacturer of this particular Linear Motion
Cassette and have any experience using it?

Thanks,

Bob Jacoby
Jacksonville, FL