Original/stock appearing Panteras seem to be fetching the higher values these days, so presumably the textured bedliner type finish might be more "valuable," but it largely depends on the buyer as it will not be "stock" and can't be marketed as such.
Personally, I prefer the textured bedliner look that approximates the original appearance. A smooth painted engine compartment looks great on a show car, but it becomes just another surface to polish and wax and worry about scuffs, scrapes and scratches if you ever put the trunk tub in there again. Just my 2-cents.
But, it's your car so you should do what you like best!
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