I am and have worked in the Ambulance service for very nearly 20 years, 15 years of which as a Paramedic.
It's a good job, very secure, depending on where you work shift patterns can give good time off, pay wise starts off a bit naff but gets better with more yeas service and progression. Downsides are you'll work weekends, bank holidays and christmas but as a bonus you get out on the trails when it's quiet. You will at times have bad episodes but you also experience some highs and laughs. Best things I like are freedom your left alone most of the time your essentially your own boss, each day is different and companionship is always good.
Fire me an email if you have any question I'll try to help, although I may forget - found an email the other day from someone I was meant to answer months back. Sorry.