I wanted to migrate my site to WPMU DEV hosting, but things weren't working. Mhamdi migrated the site for me. A minor glitch after that, which he fixed right away. Then I was able to complete DNS changes following the excellent online documentation. I've been a member of WPMU DEV for more than 5 years now. I initially joined for the plugins, but have stayed because when I really, really get stuck, WPMU DEV lives up to its pledge of support for "all things WordPress". They can't for obvious reasons necessarily provide support for plugins other than their own, but even so, occasionally I get a suggesting that allows me to solve a problem. I can't say enough good things about this company and staff.