Memory upgrade on iMac (Late 2006)

I want to upgrade the memory on my iMac (Late 2006). My present memory is 1GB 667 MHz DDR2 SDRAM. I am getting that information from the System Profiler. That (one) module is in one Memory Slot, and the other Memory Slot is empty.

The manual says the following:

+Your iMac comes with at least 1 GB of Double Data Rate 2 (DDR2) Synchronous+
+Dynamic Random Access (SDRAM) memory installed. You can add 1 or 2 gigabyte (GB)+
+memory modules for a maximum of 3 GB of memory. Memory modules must meet the+
+following specifications:+
+* Small Outline Dual Inline Memory Module (SO-DIMM) format+
+* 667 MHz, PC2-5300, DDR2 compliant (also referred to as DDR2 667)+
+* Unbuffered and unregistered+

And it also says the following:

+Your iMac has a top slot and a bottom memory slot. You can add a memory module to+
+the bottom slot and remove the memory module in the top slot to replace the+
+installed memory. You can add a 1 GB or 2 GB memory module for a maximum of 3 GB+
+of memory.+

I guess I should just do as Apple suggests and add a 2GB module to the other memory slot, to maximize the total memory in the computer at 3GB. But does anybody have any alternative experiences or suggestions? Should I perhaps add another 1GB module to the other Memory Slot so that they are both equal? Has anybody tried adding 2GB to each Memory Slot? What happens? It seems odd or unbalanced to have a 1GB module and a 2GB module as Apple suggests. Any opinions from people experienced in this would be welcome, and I thank you in advance.