Im relatively unexperienced when it comes to situations as such, so please bear with me
What happens if I install ram at 1600 mhz stock, when my mobo supports 1333 mhz? Would it be lowered to 1333 mhz with no faults, or will I have some serious issues?

Mobo: Gigabyte X58A-UD3R

Help/Advice would be appriciated

First off, make sure that the memory you have chosen is on your motherboard support list, otherwise you are taking a risk that it will work at all.

Secondly, you memory will either have to be:

A. Underclocked to 1333 MHz
or
B: Your motherboard will need to be overclocked to get the memory to run at 1600 MHz

There should not be any serious issues as long as the memory is on the support list.

The board will run all sticks at 1333MHz unless you tell it to do otherwise I've got 2000MHz sticks that run at 1333 by default.

Also, memory support lists only a small portion of memory modules that have been physically tested on the board to work. It'd be safe to assume pretty much any RAM will work on that board, so long as it's a popular brand name (not some random crud you buy for $5 at the local markets). Memory compatibility is very flexible these days.

Thanks for the help guys, I hope all goes well