I'm finally getting ready to build a cross cut sled. I want to use an aluminum miter bar. Is there any major differences/advantages between a solid bar like Rockler's and Incra's "U" channel "miter slider"? Since my General TS has a T type miter slot, would there be any advantage to go with a steel one, milled like my miter gauge so I can put a washer on it to keep the sled from tipping? Thanks. Greg