Well it's all aesthetics... and there's plenty o' polish on older vehicles... just ask anybody with pre-rubber chrome bumpers, chrome belt trim, chrome windshield trim, chrome mirrors, chrome pipes, metal door handles, wheels, steering wheels, headlight bezels, hood ornaments, grilles, etc...
The price gap on the covers is astounding though! If you're dead set on shiney peanuts but want to spend half the money for a little extra elbow grease, I'd get the classics and polish them yourself. Nothing a little scotchbrite on a rotary tool and polish can't fix up.
And while you're at it, you might as well check eBay or some used parts places for decent valve covers that can be cleaned up. Keep in mind, your shiney new aluminium is going to make everything else around it look old and tired.