I have made really good experience with a US provider called TekTonic. They have super fast and good support, I haven't had any problems since 6 years now. They recently opened a new sister-company called togglebox.com which seems even better.
Since today I have a VPS with 1 GB RAM, 20 GB disk, 2 TB traffic volume and 2 CPU cores for $14 and my minetest server performance looks very good :)
It's not a huge server though, but it seems to have no problems with 20 players or more.
Its also very nice because right now they give you $100 budget as a gift after you pay the first month.
You need to go to Order -> Cloud Virtual Datacenter then customize and order your ressources (i have the minimum + an extra CPU core).
Once you've done this you need to write to
sales@togglebox.com and ask for the $100 discount.
You can spin up as many servers as you want, of course as long as you have enough ressources, that means IPs, disks, RAM, etc.
EDIT: they accept PayPal