Anyone with experience using one of these? I am considering plunking down and getting a virpil setup going (long backorder time I assume) and this is the base they sell. Does it hold down pretty well? I see it has screw holes, is it assumed that I'll have it screwed to the desk? Not a thing I really want to do. Is it stable enough on its own without being screwed down? It looks like it would flop all over the place when moving the stick.