I've had the experience, multiple times, of buying an updated version of a piece of gear and trying to replicate the exact same sound in the newer version didn't sound exactly the same as the original in a side-by-side comparison. Either they changed some component specs, or changed the architecture / circuit design or changed component vendor/brands and the result was noticeable, though probably not obvious to all people. Either the sweep of the modulation wasn't the same, or the depth wasn't as deep, or the quality of the repeats wasn't the same, either brighter and thin or darker or unclear, or whatever. But stuff changes and if the part you liked changed, you'll notice.