One problem with treadplate is the raised pattern interfering with the mounting of clocks and the like. 2mm 5 bar treadplate is around 3.5 - 4mm thick measured at the 'treads' and while that's not a problem for switches (with some careful layout) it'll make mounting the gauges neatly difficult to impossible. Another thing to bear in mind is that (with the thinner stuff at least) the treads sorta show on the back of the sheet i.e. backside is not perfectly smooth and cut edges have a 'wavyness' to them.
Every chequerplate dash i've seen has looked like a cheap, homemade mess because of this i.e. clocks look half fitted as there are gaps between the bezel and mounting surface due to the treads and edges typically look unfinished. Granted all the ones i've seen were a cheap homemade jobby that'd slice your hands to ribbons given half a chance but personally i just don't think they work and, as said, not a material that was used for rally cars.
Engine turned/circle polished will be easier to work with (more commonly found in stainless though). Typically works best when just used as an inlay or as trim though IMO, for larger sections especially if there's much shape/several pieces i think a brushed finish is better looking
If you want something different go to B&Q and get some textured ally, they usually have a selection.