-My net speed is slow so i can't transfer 300GB Files
You can SSH in to your new dedicated server and use wget to grab the files via FTP. Your Internet connection will be of no consequence then.
But now i think Dedicated Server is good For me, this is good decision or i don't need to order a dedicated server?
Given your usage, a dedicated server is indeed the way forward for you.
-How can i find Reputation and Trusty Dedicated Providers(Already googling)
We have a Dedicated Servers section, and I'll move your thread there. It would be a good idea to browse threads there and make a list of recommended providers. Keep in mind that a server needs a server admin, so you need to either get a fully managed server, or get server admin services. I really hope you have the budget for what you need.
As inspiron ask, what is your budget? Those who are just throwing names out there are of no help without knowing your budget and exact needs. One thing is for sure, you should get your own dedicated server.
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