RAM dillemma

Can I buy two separate RAM kits at 2x4gb sticks and use them together to make 16gb of RAM?

Both of them are going to have the same brand and specs - will I encounter any problems just because they're not a 4x4gb or 2x8gb 16gb kit?

I'm go to be using the extra RAM for video editing.

It'll be fine

If they're higher clockspeeds, such as 2133 or 2400, there may be some compatibility issues and you may have to lower the timings and clocks.

Lower clockspeeds have much higher chances of working together.

They both have identical specs.. are you really sure they'll work? I'm just worried - I don't want to end up wasting money due to incompatibility, someone in Tom's Hardware mentioned it might cause instabilities and crash the whole PC.. 

Link to the ram kits?

http://www.newegg.com/Product/Product.aspx?Item=N82E16820233186

I'll be buying two of these from a friend at a cheaper price.

Those sticks are only 1600mhz.  They should match together just fine.

Thanks for the reply guys!