XP doesn't natively support the 4KB sector, all you'd get by aligning the drive is that the drive is aligned to its internal "structure".
XP still won't "think" in 4KB sectors and thats the main difference from Vista, W7 and any other OS with native 4KB support.
o.k, that's a good thing .

now, gullars,
the only thing i'm missing here is that the controller is capable of delivering ~220R to the CPU..
what you are saying, is that if the compression is at 1:2, this brings the drive, to actually operate at 440MBps read...
and that's why they were saying, windows 7 startup took ~1/2 the time to finish..

now if i understand correctly, then the data is being decompressed back in the controller when it arrives from the NAND chips,
the data is compressed, and because it's half of it's size, then the operating speed can be conceived, as double..

now the data is being pulled out of the NAND chips, going to the controller, and being decompressed there,
the data is, at it's same size again, going from the controller to the CPU, on the SATA cable, at 220MBps..

so the only difference we got here, is at the controller-NAND level,
now,
if the data is remaining half of it's size, due to the compression,
then we have double the SSD capacity actually (for 1/2 capable compressed data),
so instead of having a 100GB LE drive, we actually got something in between 150GB and 200.
so,
i don't know, if we can take it all and half it when the compression is 1/2 (or x2 or however we call it),
cause if we take the entire protocol, which means, from the controller to the CPU, it is acting the same as any other SSD (though might be a bit faster then some)
the difference, is at the NAND-controller level where i'm lost .