that's the correct performance for that drive when dealing with incompressible data.
the scores look about right. what scores are you expecting to see?
sandfarce-powered drives like the 520 will show lower than advertised write speeds when run with benchmarks like as-ssd and crystaldiskmark that use incompressible data. the lower capacity drives - especially the 60gb versions - are hit hard by this.
if you want a faster 520, buy the 120gb or 240gb version. if you want to see benchmark numbers that match the drive's advertised speeds, run a different benchmark that doesn't use incompressible data. if you want a drive that performs the same regardless of the compressibility of the data, buy a different drive that isn't powered by sandforce.
otherwise, stop benchmarking the drive to death and just use it.
Also i want to use this SSD for Intel Smart Response to accelerate my RAID 0 disks. When Smart Response turned off, my RAID Read 240 and Write 190 MB/S but when turned on, Read down to 110 MB/s and write to 90 MB/s. So where am i doing wrong for Smart Response?