The RT1900ac is the first router from Synology -- a company known for making NAS servers -- and it indeed has a lot of NAS flavors within it. Here's CNET's full review. Dong Ngo Former SF Labs Manager ...
I don't recommend this. Put your torrent server on your NAS. Personally, in a home environment, I think routers should just route, provide a firewall, and switch packets (though I don't apply this ...