Have a look on OCZ's forums, lots of users posting benchmarks where after a week or two's usage(or lots of benchmarking) they aren't getting anything close in writes to what reviews are getting, certainly not bad, at all, just noticeably lower.
Its most likely just trim not working "that" well, or maybe at all, new drives, including the Intel, Indilinx and most other drives took a while to get trim working well, get the right driver, the right firmware and the right tweaking in firmware to get performance to stay the same.
The Intel drives released without Trim support, but have it now, same for Indilinx, when you see sustained performance in terms of performance after heavy usage, Indilinx drives suffered pretty badly but are now pretty superb, same for Intel, The sandforce drives seem to be dropping off at the moment. I've got C300 128gb at the moment, it seems to be holding its performance fairly well and user benchmarks seem to suggest the same, a drop off, but not very big.
But in all honesty, I've got two indilinx drives for sale, RMA replacements as my old mobo dying seemed to trash both drives

I saw reviews and benchmarks and thought my indilinx's were so far behind I ended up with the new Crucial drive, it wipes the floor with my two indlinx's even in raid(2x64gb models) in benchmarks. In reality, it feels identical.
My drives actualy died about a week or so apart(i think the mobo dying damaged them, something happened them one just took a little longer to go). I had them in Raid 0 before, I was running as a single afterwards, I could barely tell the difference, and from a single indilinx to a (in benchmarks) much faster C300 I again can't really tell the difference.
I reall feel theres a base level of random read/write speed you need which basically gets rid of the bottleneck old drives had, stops all hanging when you try to do too many things at once and the instant access, beyond that point theres very little performance difference to feel in real world situations, while benchmarks can show massive differences.
This is , gaming, windows loading, general snappyness of windows, opening programs, basically a GOOD SSD is SO much faster than a mechanical drive in all the important bits, a great ssd is only a little better than the already way faster drives. The difference between a mechanical drive and a good ssd is obvious in everything you do on your computer, the difference between a good and great SSD, is barely noticeable.
My guess would be future firmwares and tweaked trim commands will get the sandforce drives back up to close to the numbers you see in reviews.