Best Big Sub? or duals?

Shadorne, Polar bear! Nice shot, that doesn't look like it was taken at a zoo?

I just got a D300 a few weeks ago, my first DSLR. Currently, it's a little over my head but I'm learning something new on every outing. No AF-S lenses yet just my 85mm 1.4 and a 160-600mm 5.6 I used with my trusty F3.

ok so I kind of narrowed it down to a

1 or 2) JL audio f113
JL audio Gotham g213
or 2 svs pb13 ultra's

I like the gothem the best but the price is high and I am worried about one sub having not to much of a sweet spot in the room.

I'd opt for two Fathoms. I use two now and am very happy with the sound. However it depends on how much work you want to do. If you want to set it and forget it for home theater, then if you can swing it the one Gotham will sound great, I believe. Two subs (or really one sub if you want the best sound)take some tweaking especially if you are using them for two channel only as I am. I was very impressed with the setup directions and performance of the auto setup procedure from JL Audio. The setup system from Velodyne is much nicer but one cannot run balanced cables only single ended. The Fathoms work well with my Salons and a friends electrostats so I'm sure they will work with the Vandersteens as well.

Look at the SVS PB13 U before considering anything
the Epik conquest as well. both have CONSIDERABLE output
I own an SVS PB13 and I would personally go with the ED A7-900, The Conquest or the Ultra if anything, Have no personal experience with them, danley as well.