I went from a Tama Granstar II to DW Collectors: 9mm thick birch shells in power toms to ~5mm thin maple shells in shorter depths. The Premier XPK kit to DW Collectors is very similar to what I did. It's like comparing apples and potatoes. You go from eating fruit to vegetables, yet they're both considered "produce." It took me several months to acclimate to a drum sound coming at me that wasn't what I had been playing and hearing for the past 20+ years.My previous kit was a mid-90's Premier XPK (birch/eucalyptus shells), which I thought sounded better, tbh.
We become conditioned to hearing things a certain way and when we hear something totally different, it's not familiar and the psychological aspect kicks in: "that doesn't sound right (familiar)." Similar to how a new cymbal sounds great when we buy it. It gets dirty and grimy over time and what we think that cymbal sounds like changes as it accumulates the patina. When we clean it, it sounds like what it did when we bought it, not we've become accustomed to it sounding like. Suddenly, the cymbal's sound is "wrong" or "not as good." That's another discussion for another time.