I have a 3.5 DV server and a GRID server, the DV server works great with Magento, but the GRID server is tooo slow,
DV - https://alientoinc.com/ (3 websites, about 150 products)
GRID - http://gfproject.net/ (Just Magento from the pack)
I spoke with a Suport Agent he said the GRID Service can’t handle Magento.
Media Temple is been great for 4 years for me, besides one technical support person helping me to destroy my own magento database.
My recommendation is that If you want to experiment Magento, don’t go for the Grid Service with Media Temple.
Hope this comparison helps somebody.