Memory upgrade from 8GB to 16GB on ASUS G74SX-BBK7

Hello Guys,

I am planning to upgrade my current laptop (ASUS G74SX-BBK7) for a total of 16GB memory.

I checked on crucial.com and it came up with this.

As for the use it ranges from some good (as in quantity not my ability   ) gaming, 2-3 virtual machines, graphics designing etc.

I was wondering:

Should I get DDR3-1600 or should stick to DDR3-1333?

As CPUID showed, voltage rating in my current memory setup is 1.5V. Is it okay to use 1.35V memory?

Current timings are at 9-9-9-24, will a memory with lower timings be supported by this system?

How does this one look? G.SKILL 8GB (2 x 4GB) 204-Pin DDR3 SO-DIMM DDR3 1333 (PC3 10666) Laptop Memory Model F3-10666CL9D-8GBSQ

or CORSAIR Vengeance 8GB (2 x 4GB) 204-Pin DDR3 SO-DIMM DDR3 1600 (PC3 12800) Laptop Memory Model CMSX8GX3M2A1600C9

Thanks