I took an academic job after residency, worked it for 2 years -- then moved to the community for 2 years (a personal life decision, not a professional one) -- and after 2 years after aspects of my personal life changed, left the community and went back to my original academic position.
The differences between the two are stark. Its not to say one is better than the other, but the bigger question is which one suits you best. A great majority of EM physicians find themselves in the community sector, so clearly something is appealing about it.
Here's my personal semi-solicited opinion.
ACADEMIC
I find the academic job to be more fulfilling. It is definitely more of a team environment. The ED is teeming with residents and med students thirsty for knowledge and eager to get it right. It makes mundane things for me exciting again because I get to see it through their eyes. Yes, I do less procedures and management on my own, but I'm fine with that. I mix it with moonlighting and get plenty opportunity to do stuff on my own. In addition, the staffing of the department is entirely different, with more attendings and residents around to see patients vs the community environment where its often single doc +/- MLPs seeing patients. The abundance of staffing makes even the most crazy volume shifts seem so much more manageable and less stressful. I don't feel the pressure of administrators tracking every single metric. I work with an inner city Detroit population and the ED is usually overflowing. We get through it as best we can as quick as we can, but if people wait, that's just the way it is. I think I am paid fairly and competitively, and I supplement it with moonlighting in our community satellite EDs. I work more than I did at my community job (by choice), but I will end up making substantially more because my moonlighting is much easier than my day job so I make good and easy cash. In the end, I believe I am an even better teacher than I am a physician, and this particular academic job suits me perfectly. Some academic jobs have greater emphasis on research production, etc, and you need to determine if that's part of what you want in your career. I also find it a bit annoying at times as there always seem to be meetings on "off days," something I didn't encounter in the community. When it comes down to it, when I close my eyes, I can see myself at this job, for as long as I want to practice medicine, and it will offer ample opportunity to diversify into other administrative roles if I want to slow it down but still be part of the group.
COMMUNITY
This job was a privately owned physician group that owned the contract for 4 EDs within the larger hospital health system -- and was aggresively looking to expand. I got paid an hourly rate, with a graduated partnership bonus after 2 years, reaching max potential after 5 years. Bonuses + base would've probably landed me between 400-500,000 annually. Pay attention -- first thing I mentioned is the money. Seems whenever I was talking about my job, the first thing that came up was the money -- as if it justified the work environment. The EDs were a Level 1, a level 2, a level 3, and a small community 8 bed ED. The level 2 and level 3 were often busier than the level 1 relative to staffing. Depending on the time of day, it was 1 doc +/- 1-2 MLPs. we had scribes. we would never, under any circumstance add another doc despite volumes often being ridiculous because it ate into the partner bonuses. Every single conceivable metric was tracked and your performance relative to everyone else was made public to the group. Every possible complaint was taken seriously and you definitely heard about it. In the group's defense, it ran an incredibly efficient ED and it was easy to take pride in where you worked. It was easy to get things done. But holy crap was it stressful -- from day 1 I was already looking at exit strategies because it freaked me out that I wouldn't be able to keep up at that clip for as long as I wanted to practice medicine. Every single decision was based on how much money it would make or lose the group, and whether the patient was happy. Those that stayed are making some serious bank, and overall, the docs were happy. I was an ultra high performing, chief resident who could hustle with the best of them -- it wasn't that I couldn't handle the environment -- I just didn't want to.
I've been back at my academic job for 3 months. Couldn't be happier. Feels like putting on a pair of old broken in jeans. Just fits. This is best for me -- maybe not everyone. So take my opinion with a grain of salt. But thought you'd want to hear from someone who's been in both places.