We moved all our Magento stores to Nexcess.net after several years using a variety of hosts. Nexcess is cheaper than many of their competitors and so far the performance of the SIP accounts has been good. Technical support has always been speedy, helpful and often goes the extra step to help us with specific Magento issues beyond just hosting. Just recently Rory Gallagher helped me with a database issue. He spent the time to find root cause and a solution. In a day when good customer service can be a rarity Nexcess goes above and beyond. Love working with them and would recommend hands down.