Hello,
Based on your stated profile there is a huge selection of equipment to select from. From my past research and experience I would provide the following thoughts:
1) The quality of your training and continued practice for proficiency determines how safe you are -- far more than what equipment you choose to buy.
2) Regardless of what equipment you select you should invest in a redundant PO2 monitoring system. Knowing your PO2, even on SCR systems, is critically important. IMHO, the risks of not knowing your PO2 far outweigh the cost of a good monitoring system. The only exception I would ever make was for a shallow water pure O2 rebreather and running it on loop volume... but even then...
3) Read, read, read. Read books on rebreather diving, dive physiology, technical diving, dive and rebreather accident reports, etc... Knowledge is safety.
4) Did I mention the importance of continued practice for proficiency for safety.
5) Train your dive buddies on what to watch for and what what to do in an emergency.
6) I went the SCR route but found buoyancy far easier and breathing far more consistent on a good CCR. I found over the shoulder (OTS) counter lungs were far more consistent in work of breath, but they definitely more cumbersome than back mounted. I still prefer OTS counter lungs but it is definitely a personal preference item.
7) If you travel to dive make certain the rig and equipment and required supplies fit in your travel profile and size/weight requirements. Traveling with all the equipment is the hardest part of rebreather diving from my point of view. Second is getting O2 refills. You need to do your research and plan ahead.
8) Don't ask for opinions on SCR vs. mCCR vs. eCCR vs. what-ever-else on these boards. Politics, religion, and sex are far, far safer topics.
9) Double the price of the rebreather to get a rough feel of how much it will cost for training, supplies, ancillary equipment, bailout tanks and regulators, O2 testers, cells, backup gear, tanks, Constant PO2 dive computer, mounts, etc, etc, etc, etc. If you get an very inexpensive rebreather then triple the costs.
10) If you want inexpensive don't go with a rebreather. However... doing Recreational diving with single tank OC buddies there are probably a number of ways to choose less expensive routes than most tech rebreather divers.
11) While asking for opinions on what equipment to purchase solicits a lot of responses, you'll do better just spending time reading the various threads on what problems people have had with the equipment and the manufacturers. I found this very enlightening.
12) Always carry OC backup equipment. Having an out means you're more likely to not dive when you're having a problem with the rebreather equipment. Having outs makes decision making easier and safer.
13) Find a "rebreather" experience pool session where you can experience a number of different units to see how various equipment fits and feels. I have no idea how common these are -- there was one a few months ago in Florida I would have enjoyed going to. Alternatively, try the June 16th rebreather social at Dutch Springs to talk with people and see these things up close.
Enjoy the experience!
-Paul