I've got one domain hosted with them. So far their service is reliable, and I didn't notice any down time.
I've to warn you one thing though. If you transfer your domain to them, the creation date in whois will be updated to the transfer date, and it updates every time you change your whois contact info :sad:. I opened a support ticket with them, but their response is just unintelligent, basically telling me their system is like that.