You are correct about the limit of your computer, but there are other stuff to consider when buying a SSD as well. The random read/write are normally much lower than the sequential read/write, but the manufacturers often just specify the max sequential read/write. Your computer should be able to handle the max random read/write speed even if you pick the better SSD's like the Intel X25. If you decide to buy a cheaper SSD with a lower sequential speed the random read/write speed are most likely much lower as well compared to a better SSD. In that case the SSD will be the bottleneck and not the SATA even for the R61.
There are other things to consider as well like get a SSD with trim support, NCQ support and a SSD that have functions to limit the wear level. Also if you buy a new computer in the close future you most likely want to move the SSD to the new computer. Then you will most likely regret not buying a better SSD.
So i would recommend to spend some extra money on a real SSD and not the cheapest models. I'm not talking about a $2000 SSD, but for example the Intel X25 G2 SSD's are among the best and not that expensive compared to the slower models. I also trust the reliability and quality of the Intel SSD's and others that are known to create great SSD's. I'm not sure i would trust the cheapest SSD's available even if i don't have any proof to support such a statement.....just a feeling
-gan
