I've played the Plat's and they are nice, decent sizes to pick from, drums sound nice, comfortable playing, but a couple things will make me say the Centennials are nicer.
The style of the Centennial's floor tom legs allow for easier drum and stand placement because they don't span as far out.
The finishes on the Centennials are done nicer IMO than any of the different Platinum finishes I have seen.
The lugs on the Platinum's seem a little cheap to me, and the spot where the rubber of the mounting band touches the shell CAN rub the finish off (been told it's happened a few times by my drum shop guy's). The mount itself is pretty nice though, and I do like how it's close to the shell (possible finish problems aside) for placement.
The wood on the Centennials is the same wood/grade of Maple used in the Classic Maple (& Legacy) series. I have no idea what grade of Maple DW uses for the Pacific line.
I personally would prefer the 20" deep bass drum (it's a magic sounding size for me on any diam bass drum) but it might not be for everyone.
There's no mount on the Centennial bass drum which I like--The Platinum can come either way, but if you had to order a Virgin kick separate, but your shop has a kit with a mount....you could be waiting or just end up getting something you may or may not want.
The Centennial is a shell pack, so you can use whatever hardware you want, and the lugs and screws Ludwig uses is a heavier grade compared to some other brands I have taken apart. I have no reason to believe the Centennials would be any different, and Ludwig is good on the 'beefiness' of all their parts--and Ludwig's tom mount/ft bracket is actually a little bit thicker than a DW or Plainum mount.
Ludwig also has a pretty extensive parts catalog and Centennial parts are in it now. Should anything happen to a part, it'd be under warranty (for quite a while) and the part would normally be in stock--not that I'd expect anything would be wrong with a Centennial purchase.
Their delivery time is pretty quick, I've no waited longer than 2 weeks for anything that was a "part" like lugs, floor tom legs, mounting brackets or claws when I ordered them for my various projects.
Add-on drums in the Centennial series are VERY reasonably priced.
The Platinum's do sound good, and I doubt that if I did have a Platinum kit, that it wouldn't sound nice, but all things taken into consideration, and the great sound of Ludwig's maple shells, I'd go with the Centennial's.
Yes, I admit that I am big on Ludwig, but it's because in the 30+ years I have been playing Ludwig stuff (AND other brands, not JUST Ludwig), I've said it before, & I can honestly say that I have not had one problem with anything I've gotten from Ludwig other than one floor tom that wasn't as Black on the paint job as my other drums, but they took care of it pretty darn fast. I remember it maybe took 3-4 weeks.
There are other great sounding and looking drums out there, but Ludwig has never given me a reason to really want another brand.
Sorry for the book.