Those prices seem ridiculous to me. Where are you located?
If you live in the US or Canada you should be able to find much cheaper triple channel kits. For example, I've listed a kit that can be found on newegg.com below.
G.Skill CL8 DDR3 1600 kit for $154.99 USD: http://www.newegg.com/Product/Produc...82E16820231304
EDIT: The site that sells that particular G.Skill kit is located in New Zealand, so I'm going to guess that's where you are located. Scratch the newegg.com link!
If you're willing to spend the extra money on that G.Skill kit, then go right ahead. DDR3 1600 and CL8 should provide great performance.