I used to get frequent downtime from them when I used dedicated machines, about 4 hours a month. These days I use their VPS for staging environments and gitlab-agents.

I don't use them for gitlab or production because they do not meet the uptime/response time standards I require (300ms pings from Toronto to their Montreal datacentre).

They are cheaper but if the above is more important than raw power then I'd go elsewhere.

Edit: I haven't used their Public cloud offering yet, that might have improved performance over their dedicated boxes and cheap VPS.