Because they can make money selling ssd's to value buyers who don't know any better, after all, many of their published specs (with an empty drive) are virtually the same as the high performance models. I fault most of the manufacturers who seemed to hide which type of NAND has been used in many or most of their models. I think that the TweakTown ssd reviewer was the first one to report on the consistently inferior asynchronous performance. Quite a few forum members got suckered into buying these lower performing drives.
Why some SSD manufactures are still using asynchronous NAND is beyond me, and on some of their latest models.
AnandTech - Samsung Releases TLC NAND Based 840 SSD is a quick read that covers the new Samsung 840 Pro and TLC model introduction. The bottom line is that the Pro models have higher real world performance, a longer warranty and cost about 30% more than the TLC models. I'm impressed with the fact that Samsung ssd's have significantly fewer reported problems with firmware stability and don't have anywhere near the number of reported problems with stuttering or ssd's suddenly not being recognized by the motherboard.
Ssd prices are quite low right now, and there is currently a surplus of NAND memory, so much so that several major NAND manufactures have significantly reduced NAND production to better balance supply with demand.
For today only, Newegg has a "deal" that ends at midnight tonight for a
I checked out several reviews and it uses asynchronous NAND and it's real world performance is at the bottom of the ssd barrel. It's performance is far better than hard drives and it will probably be fine for someone who doesn't need top tier performance for their lower end, middle of the road system.
Kingston SSDNow V+200 KR-S3040-3H 2.5 Inch 240GB SATA III Internal 7mm Solid State Drive (SSD) (Stand-alone Drive)
$129.99 after a $30 MIR (with a promo code and with free shipping)
It would probably be fine for my current dual core systems as long as I only used no more than 40 - 50% of it's capacity. I've never had any problems with any of my Kingston hardware and this ssd should be as reliable as other similar lower end ssd's. With luck I might be able to find an inexpensive sata3 controller that will let me get half-fast sata3 speeds with my new drives.
I hate to say it, but I think that I just talked myself into buying 240GB asynchronous sata3 ssd's for both of my five year old systems.
I'm planning on building an overclocked Haswell system next summer so I'll buy a higher end ssd at that time when I'm ready to build my new system.
just my 2 cents.....
Never mind, I'll save some money and buy two Samsung 830 128GB ssd's for about $90 each and not even bother with a mail in rebate.