I've had exploring mxroute as a low-priority todo item for a while, I like that pricing is roughly per gigabyte, not per domain or per user. Do you use it? Does it deliver to gmail and others ok, or does it go to spam?

I've used it for years, no issues with delivery to gmail or outlook.com / o365. They've got a bit about their delivery system mentioned here: https://mxroute.com/docs/#/Presales/ipreputation

It's pretty basic in terms of webmail/core functionality but it receives and delivers mail well from the various IMAP clients I use, which is all I need.