Obviously, I don't know where you live, so I can only offer some advice based on where I am from (which includes rural voluntary, rural staffed, metro staffed, and city staffed).
Typically, EMS clinicals require X number of hours in different fields before you are even allowed to take finals. For us it's 4 hours nursing home, 20+ hours ED, and 20+ hours ride time (with A and P needing X hours of contact time with peds). Even this can be good because you will have exposure to a variety of fields in medicine (geriatrics, peds, and so on). Huge cities will also give you the (dangerous) opportunity to explore gunshot/stabbing wounds. Plus, depending on the city, you work there, you can get a job anywhere. (*cough*Detroit*cough*)
The station I am with only allows EMTs to get 20 hours a week. Obviously, you need more income than that to live. If you can find a station like that and can get a consistent schedule, it's along the lines of a part-time job (with the understanding that it could be extended for hours if you get a major page five minutes before your shift ends). If that's a concern, overnight shifts might be good, depending on your area.
Our cost per student is $1050 (textbook included) but it was paid for by one of the agencies. In our area, yeah, you can get in if you have the money, but it's a good idea to have a sponsor, especially since an agency sponsor will automatically cover you for liability whereas unaffiliated students have to find their own insurance. You'll want to look into insurance policies in your area. This way, not only is the money coming out of someone else's pocket, but you might be reimbursed for gas. On top of that, if an agency is investing $1000 in you, they're going to want it back, so there is the potential to get a job with them afterwards, even for a short time. However, as it has been mentioned, competition can be vicious. In my station, we can't find anyone to hire. No one. At all. So I'm pretty set. But in the city, where we are, with jobs like they are, you really need good experience, which being in medical school could give you a leg up. Depending on who you go with, they may or may not like that you just want two years.
Our area does shifts by twelve-hours, 12, 24, 48, and 72-hour shifts. A lot of this will be rig checks, equipment checks, and waiting for tones. Sometimes, you will be stuck at the station with a partner you really don't like.
As for enjoying or not enjoying, don't be a jolly volly. Don't look for the movies or the explosions or the dramatic music. Yes, you will be paged out to nursing homes for lift assists; it will be two minutes worth of call and ten minutes worth of paperwork. You'll be paged out priority 1 shortness of breath, chest pain, and it's a skinned knee (because shortness of breath and chest pain get a faster response). You will get old people who just want a social call and young people who just want a ride downtown (this was an epidemic in our area a year or two ago).
Personally, I worked in a nursing home for four months. It wasn't glamorous and it was often very stinky and about as thankless as you'll ever get. The work wasn't particularly bad because some of the residents were just the sweetest people, but the politics was overwhelming. And you will get that with whatever agency you work with, whatever job for that matter. Sometimes it is personality and other times it's just internal strife as everyone wants funding and whatever is going on. If you can step back and say "Not my circus; not my monkeys" and just go on the calls and do the job, you really will be all right.
Basically, there are a few questions to consider:
1. Can you handle blood, guts, vomit, feces, and other bodily fluids?
2. Can you handle two-am pages for a twenty-minute bogus call (or a four-hour life-and-death call)?
3. Can you shell out the money for only two years of a job?
3.5 If you can find a sponsor to pay for the class, are you willing to potentially work for them on their terms afterwards?
4. Can you handle days where you will in fact be wiping people's butts?
5. Can you handle spending twelve hours or more with someone who you may not like?
5.5 Can you put aside your differences for the sake of the patient?
And, ultimately, talk to an EMT in your area. Talk to a basic, an advanced, a medic. Ask them what it's like, why they're there, what makes them stay (or what made them leave if you can find a former EMT).