I am planning to buy Raspberry pi 2 Model B. Predominantly for two purposes,

i) Download Box (for Torrents, ftp / http downloads)

ii) Web Server (For replying some requests to Local Client computers ) and sometimes it will be used as an intermediate to share files between devices inside Lan with an attached HDD to it.

Please note that it will be 24/7 powered on most of the time and connected directly to the router via ethernet cable.

My budget is maximum $40-45. Will raspberry pi perfectly work for this purpose? or any other board would you suggest? If you have used it, what average practical internet download speed do you get?

UPDATE: I have 12 Mbit/s internet connection plan. So, I expect getting practical minimum download speed of 1.5 MB/s.