^^ Darn Straight.
One thing I see fairly often is people skimping on their pump. They will blow a ton of money on a huge rad, and then buy a $30 pump. VERY counter productive. You need to build a system around all the components, and possibly the biggest component to consider is what pump you are ruuning. That directly affects what you can really do with the rest of the setup.
Like Sewer said, Simply saying "Get a bigger rad" may not be the right answer. It could just be a big waste of money. The poster said he is considering a Hydor L30. Not a bad pump, but not a top performer either. With a CPU and GPU block in the mix, and throwing in a BIX3, he's going to murder his flow rate, heck it is possible he could see HIGHER temps with the larger rad simply because of loss of flow rate.
If the poster goes with a D5, then yes, that shoudl be powerful enough to see a potential performance increase with the BIX3. If he does not however, and opts for the Hydor, a better bet would be the BIX2.
And in all honesty, a single pass HC woudl be an even better bet.