In order to find the top managed server providers, you have to create your own list in accordance with what you prefer. You may consult the list provided via the net for reference and visit the company profile and the things they can offer. If you find something on that company that you might need in the future, and then include it on your list and so on and so forth. Sometimes it is not wise to rely on the reviews of certain providers; you have to investigate further in order to be certain. If there are negative comments on that provider even if it is a kind of black propaganda you will know for sure whether it is true or not if you will conduct the research yourself.
Finding or looking for the top server provider might eat up a lot of time for there are many companies to choose from. Consider a friends recommendation especially if he or she is catering the services of that particular provider but also look at the requirement of that friend because it might be different from yours. There will always be difference in price because not all people have the same requirements for the server.