its a tough call Rod, I do know the place I deal with directly (Microcenter) have stores across the continental US.
they and a lot of other places that sell RAM (like New Egg, Exc) will allow you to return it if you find it "Defective" per say. some places wont even ask, just simply send it back and get your money back. Its hard to say with RAM, especially considering the each of us work individually in different ways. Some of us use a large amount of soft synths/sample library's, mixed with Audio tracks. while others use a ton of soft synths/sample library's which determines a large amount of how your RAM is being dispersed.
Back to my original suggestion, Order the RAM and give it a test run. if you don't like it, return it and get your money back. kind of a no loss situation. I've built several DAW's in my time, both AMD and Intel and I have found Intel to be much more expensive and for years I battled with the assumption that the money was not justified for the extra price of an Intel. but after this latest build (I build back in April) I have a different opinion. I believe the extra money is well worth it for the Intel. they just seem to process everything so much faster.
I built a top of the line AMD build 3 years ago and it was fast. I had many debates with Jim Raseberry over the differences between AMD and Intel and I still stick by most of my theory's but he was right. Intel is far superior to AMD. though I will give AMD the upper hand when geared toward some of the gaming systems.
but were not playing World of Warcraft here
when your ready to upgrade (even if its in a few years) call me, I'll walk you through it.
we'll get a list together and build it from scratch. trust me I was in the same situation. I saved for almost 2 years putting change aside, extra money, sold one of my desks (Tascam M-50) and did it up good.