Don't have my flux Delta+ yet so take this with a grain of salt, but I do have a vinyl cutter (well more like a anything that's reasonably flat cutter... It's a cricut).
The blade likely won't be particularly long and vinyl comes with two layers, the vinyl which is sticky and the backing which is not. As long as your depth is set right you should only be cutting the vinyl and not the backing - so the plate shouldn't get touched unless your depth is off.
The biggest trick is the vinyl itself. If you get Oracle or printable vinyl which generally sells in flat sheets, great. But most "fancy" vinyl (glitter, "holographic" air quotes because it's more irridescent than holographic, chalkboard, whiteboard etc) it often comes in rolls. Which means then when you cut the piece you want to cut from it still curls.
Having some kind of sturdy tacky cutting mat you can attach this type of vinyl (with it's backing still on) to in order to keep it from curling or shifting while the blade does it's work would likely be a good idea (and adds a third level between the blade and plate). And you can attach the mat down to prevent shifting with out interfering with the vinyl you want to cut this way.
I was thinking I'd likely sacrifice one of my older cricut mats which is past is prime or suffered from a depth misadjustment (oops...) and cut it down to suit once the flux got here - to try out the cutter and see how it tackles different vinyl types/thicknesses.
The cricut will likely remain my primary cutter though.
Being able to cut 1ftx2ft designs at a shot, multiple layers in different colors at the same time for layered designs, being able to draw and cut at the same time and the design software isn't something I would expect the flux to compete with.
But I like the idea of having a back up with the flux for easier / smaller designs.