Stable server provider ... what should I do?
 

Which server is better to have a deal with - hostround.com or hostsailor.com?
Any ideas?

I've never in my life had so much technical support. DataPacket.net is reliable option to deal with. The service itself seems to be faster than other hosts I've used in the past. I would highly recommend this web host.

KVChosting.net and legionbox.com servers are well-balanced and cheap.
Never regret my time with you guys. Money is well spent if you ask me.
Awesome top-notch hosting is available from them.

Any specific server location? Apart from storing your site, what services will you need from your hosting provider?

Well-balanced dedicated servers you can get from
1) ZakServers.com
2) KVChosting.net
3) Digitalhost.com
Nice reliability, easy to use control panel and excellent customer support.

Plans from planethoster.com are full of useful resources and uptime is high and support is active around the clock.
They are 100% reliable, their hosting services are reproduced with great precision testifying to a perfect ability to work.