Recently I had a discussion with a colleague about the usage of Windows Server editions in our test, demo and training environments. I stated that I always use the enterprise editions, (because I can) but did not have a solid reason except for the fact that I sometimes demo clustering and things like that. My colleague argued that he only uses what he needs, and that this was the standard edition unless he needed a feature that required Enterprise edition. That is a good reason I thought.
Investigating an issue another colleague ran into recently, I ran in to the following KB article. The issue was with a Server 2008 Standard edition VM running on Windows Server 2008 R2 SP1 host in Hyper-V. I set it up to use Dynamic Memory, but it did not use Dynamic Memory. so I use my best friend Google to check up on that: I found this KB article: http://support.microsoft.com/kb/2230887/en-us
Here it states that there is an issue for both Server 2008 standard edition and Web edition in relation to Dynamic memory. Luckily there is a bugfix for it that will become generally available in SP3. But I am very happy now, knowing that my choice for enterprise edition made that I never experienced this issue before.
I think I will stick to using Enterprise edition for my environments.