With that much Emotiva gear Ollie they should have given you an XREF sub for free. I've read good things about HSU, Emotiva and SVS subs. Since you have a lot of Emotiva gear already just get the XREF sub to complete the set. If you don't like it send it back within 30 days.
For me I like Velodyne but if I didn't have Velodyne subs I would go for SVS subwoofers.
For me I like Velodyne but if I didn't have Velodyne subs I would go for SVS subwoofers.