@ yonef : Read/write speeds aren't all what SSDs are about. You get them for the crazy fast access times, which HDDs can't come close to matching.
Your comparisons don't make sense anyway. This is for the portable sector. You wouldn't slam a mobile GPU just because there's tons of discreet ones that can beat it. Are you seriously implying that a 3.5in HDD will fit in a laptop?
These are designed as small drop in upgrades for users who want an SSD boot disk along with another drive. Sure, you could put the m4 in and get better speeds, but most laptops don't have 2 drive slots. There are plenty of slower SSDs - these will be the fastest mSATA drives on the market.