lol.. just another brand basher there^, NTAC.
Disregard if the milions of others using that Sandforce drive are any evidence to the matter. I have 6 Sandforce in R0. And those are the ones that are much more likely to panic lock than the newer version you're looking at here... so go figure.
Want a more unbiased approach?.. look at each drives intended usage and go from there. Sandforce 2281 will be faster overall than that Marvell drive due to the internal compression ability. However, that average falls with any asynchronous nand equipped SSD like the Agy3. If you push even further to a worst case scenraio through heavy writing of pics, vids, music and tons of streaming HD on a consistent basis?.. you'll want the Marvell controller.
Even if you did push that workload onto that Sandforce though?.. it would just require a bit more idle time recovery, is all. GC allowance is far better than TRIM alone on those drives. Although, the Marvell is no sweatheart in that dept, either.
Other than that.. it's all just a matter of what you want to pay, intended usage models, and brand preferences. Both are similar enough in average workflows. Good luck on the hunt.
PS. to actually answer that question.. no, not really going to notice much difference between a good sata2 SSD and a good sata3 SSD in overall usage. This is because overall usage speed is all about random file performance and latency for an OS volume. I've used volumes with tall sequentials and mediocre randoms/latency and they are certainly not faster than the opposite would be for an OS environment.