One nice thing is that DDR3 ECC RAM is extremely cheap. I bought 32GB of RAM for $60, and have since seen 64GB for $85.
Also, it will boost to 3GHz on all cores at once, as long as it stays cool enough.
My experience mirrors the article and your experience. Fantastic value for a really great workstation! I happily run several VMs for dev work, the usual IDEs and switch between games with zero issues. I picked Noctua coolers, same as the article, and the noise level is also excellent.
I was initially considering a new Xeon E3 system, because I wanted to have ECC memory, but the price on these used components had a significantly better price/performance ratio. Whenever I decide to update to a new system, I'll be looking at something like this again before I consider something new.
Edit: Should mention that Supermicro has proprietary ATX/E-ATX motherboards. I went for them because I thought it would just work with an E-ATX case, but I ended up drilling 5 or 6 holes in my case for the standoffs.