If we're allowed to talk about units other than the JJ or Meg, I'd love to talk about the Fathom. I really think it's one of the best units on the market right now and love mine immensely.
Please understand, I *AM* an instructor on the unit and I am friends with the manufacturer, I am being upfront in case anyone says I have bias, but here's why I love the Fathom:
1. Simplicity - it's brilliantly simple. The head is a work of art and incredibly simple. Being an mCCR, there is not a lot in the way of electronics / etc in the unit, but this simplifies the whole process. Passive O2 addition is handled through an adjustable needle valve.
2. Clean - the unit uses back mount counter lungs, so you don't have the clutter of over the shoulder counterlungs. Charlie uses a nylon line to lock the head down, so there are no latches that could potentially break (and it is a bit more streamlined).
3. Non-reactive canister - The Fathom uses a black amalgam canister that will not corrode. It's also nearly indestructible, you can take a ball peen hammer to it and it will not dent or crack (and I've tried this experiment!)
4. Flood tolerant - In the event of a flood, the T pieces direct water into the counterlungs which can be quickly de-watered.
5. Little things - Charlie put a lot of thought into little things that all add up. For instance, the cells are oriented in a way that while diving, moisture stays off the cell face and pressing the DIL mav causes dry gas to blow across the #1 cell face for instant verification. Inflation hoses are custom lengths, to provide optimal routing and positioning. Loop hoses are very flexible to provide full range of motion. The HUD is beautiful and readable in bright daylight. The kent tooling brackets are capable of supporting heavier cylinders, so you can slap a couple of LP50s with LOLA valves on it to provide fully redundant DIL / BO gas in a clean package for jumping off a boat.
So if you're willing to look at other units, I'd encourage you to consider looking at a Fathom.