Rebreathers

[Dive time]

You really have three choices, one the Meg, two the Kiss, and Three the Inspiration.  All are very good units, and each work the same with some small differences.  For example, the Meg and Inspiration are controlled using electronics.  That means that you will have o2 added to your breathing loop electroniclly.  The Kiss is a manual unit and o2 is added by a constant feed orfice and a manual add valve.  The Kiss you will only be able to dive to 300' before you would have to add a electronic 02 add system ( hammerhead).  The Inspiration and meg, are being used deeper than 300'.  I personally have the Kiss, and it wont really matter what one you choice, because they all work great with mixed gas, and the breathing resitance is better that OC.  I personally will never go back to OC after diving the CCR.  

You need to take a look at each unit and find the one that best fits your diving needs, and future needs.  My only regret is that I can't go deeper than 300' because the Kiss will not add 02 after that depth.  However I just returned home from diving in Two Rivers and dove some cool wrecks, to 220', and I have had the unit down to 250' and I would say that I not only had no problems but the unit was easy to fly, and great to breath from.  

Just my two cents.  
Look, learn, try, read, and decide.