Need to buy a stable server ...

Servers from planethoster.com and owned-networks.net are attractive for me and I wonder which way I should go and why?

A dedicated server is necessary for those who incur losses at the slightest downtime of their site. How many resources do you require?
Check out well-balanced dedicated servers offered by Zakservers.com and also Swisslayer.com web hosts.
They also allow integrated email communication with their support tickets which is a time saver.

OwnWebServers is offering a special sale on their dedicated server hosting plans. For a limited time, you can enjoy a discount of 55% off your purchase by using the code EASTER55 at checkout. This is a great opportunity to upgrade your website's performance and reliability without breaking the bank. With OwnWebServers' high-quality hardware, advanced networking infrastructure, and 24/7 support, you can trust that your dedicated server will meet your needs and exceed your expectations. Don't miss out on this exclusive offer - act now and save big on your next dedicated server!

I'd recommend you to try deals from time-tested companies: hostingsource.com and hostsailor.com.
The pricing they offer also made a huge difference when selecting a web hosting company. The service is really good. Just tons of value. Plus, their customer service is absolutely outstanding. Nothing more I can ask from my web hosts.

It would also help if we have your hardware requirements, that way we can bring proper assessments.

It is a good idea to speak to web host's representative to make sure that you'll receive exactly what you need.

What I want to say is that Datapacket.net is quite good option for hosting websites.
They even have nice scripting extras and spamassassin.
Great features.