The two drives (a 20.5 gig and a 27.3 gig) both have 6.8 gigs per platter, with 3 and 4 platters respectively. The model numbers of these drives are WD205BA and WD273BA. But wait, what's this? I found a Storage Review article that reviewed a new Western Digital drive with around 10 gigs per platter, and two platters for a capacity of 20.5 gigs. More gigs per platter means higher data density, hence better performance, so I started looking for the 10 gig per platter drive. And this is where things start to get bizarre.
You see, as Storage Review points out in their review of the drive, this two platter, 10 gig per platter drive has the exact same model number as the 6.8 gig, three platter drive. But wait, it gets even better. For whatever reason, the new 10 gig per platter drive is part of WD's Caviar line, which is their "value" line of EIDE drives. Never mind that this particular Caviar drive whips the snot out of the current top dog of the Expert line. Scratching your head yet? Me too.
In theory I should be able to find one of these 10 gig per platter drives by looking for a 20.5 gig, 7200 RPM Caviar drive. I managed to find one store which claimed to have one, but that same store also claimed to have a 27.3 gig, 7200 RPM Caviar drive, and guess what? Those don't exist.
So I'm left twiddling my thumbs wondering if there's any way I'll actually be able to get one of these puppies mail-order without ending up with the older drive. I can just see myself calling a vendor and asking them not only to confirm a model number, but to open up the drive and see if the word "Caviar" is printed on it. Let's give a big round of applause to Western Digital for their creativity in designing new ways to confuse consumers. Now excuse me while I go buy a Maxtor.