The Intel® Core™ i5-460M Processor inside your Vaio is limited to 8 GB RAM of DDR3 800/1066. So you can substitute with 2x 4GB DDR3 1066 to reach the maximum size.
If the Crucial 1600 MHz RAM would be compatible, i guess it will be underclocked to 1066 MHz.
Btw, according to your laptop's Marketing Specifications, there is 2x 2GB DDR3/ 1066 MHz built in, not DDR3 800.
I recommend upgrading to SSD also, because this will really speed up your system and has other advantages especially for laptop usage like less power drain in battery mode and higher shock resistance.