re: spray on chrome, it does look the biz/kinda like the shiny side of tinfoil but is so impossibly hard to get it to spray properly most people wont bother (i did it and it looks like glossy brushed aluminium because i suck)
re: stick on chrome(the good shit) looks awesome but bumpers will need to be painted silver first as its transparent so you cant go be to carbon if you change your mind