Only one answer to that problem...PRIVATE TRACKER. I have been able to max out my connection with enough seeders, that's only possible on private tracker. Anything public and you are asking for slow speed, even usenet is technically speed limited based on the server.
Edit: Almost forgot, youtube can max out that 150mbps as well, only in 1080p though and it must be a rogers toronto server and it must be off peak hours lol, otherwise its about 25-100mbps as it varies a lot