Martin Logan Dynamo versus....

I had a Martin Logan Dynamo sub and sold it because it didn't integrate musically very well with my speakers. It would occasionally belch out dissproportionate growling low tones which although great for home theater stood out like a sore thumb with music. However my MJ Acoustics REF100 sub blended in perfectly with my floor standing Dynaudio 220 speakers and were more than adequate in a large living room. I had given up on using a subwoofer and didn't know a sub could sound so good. If you want a sub primarily for music and home theater is a distant 2nd consideration, you can't loose with an MJ Acoustics (or REL) sub.

I'm never tried the ML dynamo. I have tried the MJ 50 with Martin Logan CLS 2z the seem to integrate well being very fast.

While I think the Dynamo is a nice sub, I prefer the REL Q-108 and the smaller MJ Acoustics. I am using a MJ Pro 50 right now. They seem to be easiler to intergrate with my bookselves.

easily 80% (that's no understatement or joke) of the performance of the subwoofer in a room is acoustics, possitioning (in relation to seating area), and setting the crossover, phase, and level matching!...as well as often EQ'ing. Bass is the single hardest thing to get right. Case in point:
I just calibrated and re-engineered a 7.1 system for custom installer who'd been installing systems for 15 years solid. He had two very good subwoofers in his system, and yet the bass was AWEFUL!!! The subs he had setup (poorly I might add) were the superb M&K MX5000 THX and Earthquake Supernova 15" subs. Basically, the subs where ill-placed, the volume levels way too high (and different between the subs no-less), and they were OUT OF PHASE!...YEIKS!!!
If you place any sub in a corner, it's going to excite the bass modes in the room, and make it sound boomy, fat, bloated, unatural, unaccurate, and 'low-fidelity!" yes, you'll get more output, but that sub needs to be EQ'd, at the very least.
It's easy to say, oh, well, this subs's better than this and that. But, bottom line, I could take the worst, loosest, weakest sub on the market, and make it sound better from proper setup, than the best subwoofers ever made!!! However, ofcourse, you can get much better potential from a properly setup sub.
That all said, I'd say you need enough sub(s) for your acoustic space (consider openings to other rooms). Most people "under-sub" for larger rooms open to the rest of the house. It's a BALANCE, indeed.
You're going to have to try subs in your system, with your level, otherwise get some help. good luck