I would say colocation is most reliable. I'm sure dedicated VPS is better but most still reserve the right to pull the plug for hardware replacements. Colo isn'

I would say colocation is most reliable. I'm sure dedicated VPS is better but most still reserve the right to pull the plug for hardware replacements. Colo isn't terribly expensive if you buy used equipment. Really consider how important 100% uptime is though. Google and S3 have gone down multiple times without killing the internet or losing a ton of customers. Plenty of large SaaS providers still use maintenance windows. Heck, GitHub went down today. Not sure if you use ADP but that goes down for a couple days a week! I know it's not the popular thing to do but you can get much better relative reliability by running a single database per tenant and running a limited number of tenants per VM.