Martin Logan subwoofer - Dynamo or Grotto?

I'm looking to pick up a subwoofer to mate with my Soliloquy 5.0s. I am set on getting one of the Martin Logan models, and am wondering if I should just a Dynamo because they're more readily available and cheaper or should I wait for a Grotto?

I don't need a lot of SPL in my 12 x 20ish room. If anyone has any reasons why choosing one or the other would be better I'd be interested.

Happy listening!
Both are excellent subs. I own two Grottos, a Depth, and a Dyanmo all installed in my theater room which is 14 x 18.

I perfer the Grotto over the Dynamo. The servo controls in the Grotto makes it a bit better sounding for music and movies in my opinion. I am also considering selling the Dyanmo because four subs is a bit too much in my room.

Good luck in your search.
Thanks for the reply!

Great to hear from someone who has owned both models. I wish that the Dynamo's controls didn't end up under the sub when it's in front firing mode. I live in an apartment now, so I would like to have easy access to turn the sub down if I'm listening later in the evening.