I have some of the IBM 60GXP's and they benchmark just about the same as my 75GXP's. Since there are a lot of different parameters to measure such as access time, data rate etc etc you can have different results with different benchmarks that measure or weigh certain aspects more or less than other benchmarks. In just about all respects the 60GXP is very close to the 75GXP. It is however Considerably quieter and the tone of it's noise is much less annoying than the 75GXP's (which aren't all that loud anyway). If you like quiet, get the 60GXP's. I don't think you will be able to notice any performance difference from the 75GXPs.
DO NOT GET THE NEW FUJITSU DRIVES! I have 4 of them currently and they all SUCK. The Fujitsu Drive that Tom reviewed was the MPG3204AH-E and he got pretty good results. HOWEVER THAT'S NOT THE DRIVE YOU WILL GET IF YOU ORDER ONE. All the drives currently in the distribution Channel are MPG3204AH's with no -E revision. These drives are VASTLY slower in access time, about 60% of what an IBM 75GXP is. The drives are very quiet, but the small block access times are Dreadfully slow, up 3 times slower than a 75GXP. If you get an non -E revision drive you are screwed because you can't return it for -E revision. Fujitsu refuses to exchange it for a -E revision and I have tried at length.
All the Technical info of Fujitsu's web site references the -E version, there is no mention that any other version even exists nor do they publish the specs for PoS drive they currently have in the distrubtion channel. I guess they are hoping nobody will notice.