What kind of site are you intending to run, all UK companies are going to be required by law not to allow some kinds of content so you might as well be open with what it is you are looking to host from the start so people here can point you in the right direction.
One thing to note that with a managed service the provider will be looking at your server from time to time to do work for you on it, with recent cases this means that if they find something illegal or copy right infringing they are required to act on it themselves or may be liable.
What was be useful would be to know what the site you are looking to run is, your disk, ram, OS and control panel requirements, along with a budget - this way we can suggest things more likely to fit your needs
Since this is illegal due to copyright infringement in most countries, you're going to have problems finding a reputable host that will allow this on their network.
^^^ i think that pretty much says it all. If it's illegal in your country you can be ordered to take it down, a lot of countries will also honour court orders from abroad and take down your VPS if there is illegal content on it.
if it's illegal my advice would be.... forget about it!
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