Hmmm, wouldn't that depend on how much your paying for hardware? I honestly doubt someone would pay a lot of money just for a 3DS video conversion website lol? unless said servers are already his/hers and are being used for multiple things. Plus, the fact that upload/download makes things slower does make it a less effective system. Also, any sort of problem uploading or downloading the file could could screw up the entire source or result, making the whole process worthless. A person with a decent Phenom II quad or hexacore could probably out pace this entire operation, and those are older CPUs (But the hexacores a are pretty amazing though For people with crazy Internet connections but with horrible computers (which in my opinion is self defeating), this should be pretty good.Servers are often set up just for number-crunching, so they'll almost always be at least a bit faster than home computers.
But the upload and download can often take longer than the actual conversion process, tossing that benefit out the window.
Edit: This seems to be a full on conversion site. The hardware should be good, but everything else still applies.