[bibouthegreat]

Those guys do a pretty good service. They have presence in London (Brick lane) and Midlands. They also do dedicated servers. https://www.veloxserv.co.uk/

Remember that a colo means that if you have a hardware issue, you have to go there so have one close to you. Otherwise, there are "remote hands" you can hire per hour.

Also, if you don't have a specific hardware need, it's likely that a dedicated server would be enough. If there's a problem, you always can swap it for another one in a very short time. If it's our hardware, you're responsible of everything and that might not bring any positive point on your side.