Olydog:
I've been doing helo EMS for the past 3 1/2 years, and I'm having a blast.
I'm not sure what you mean when you say "currency." I hadn't flown a helicopter in 11+ years when I applied to the outfit I work for now. 4.1 hours of company flight training in a B206L later, I was assigned to our then newest base in Eastern, KY -- as the lead pilot. To be fair, our training program has evolved into a much more comprehensive and professional undertaking since then.
QOL, in my opinion, depends on how close your base assignment is to your home. A normal schedule is 7 days on, 7 days off, alternating between day and night shifts. If you're lucky enough to be assigned to a base within an hour's drive of your home QOL will be great. If you're assigned to a base far enough from home that you have to stay there for your entire 7-on, QOL is not as good; however, if you're working with a good group of people I wouldn't call it bad either.
Pay range depends on helo EMS experience and -- if a union isn't involved -- your negotiating skills. Somewhere between 45K & 50K to start, with an additional 1.5K per year of helo EMS experience is about routine.
You mentioned Memphis in your post, so I'll warn you that TN requirements are onerous compared with other states'. The TN minimums are 3,000 hours total time, 2,000 hours helicopter PIC, 1,000 hours turbine helicopter, and 200 hours unaided night time.
If I can be of further assistance, feel free to PM me.
Good luck & Semper Fi,