Pros
Good work-life balance for analysts. Can be a good place to get your foot in the door of the intelligence community--just don't stick around too long. Employees in the analysis career field have the most potential for promotion, but the HUMINT or Science & Technology career fields are where I would apply if I could do it over again.
Cons
Prospective employees--you really need to understand the promotion process here. It is very different from any other agency. First, if you are being hired from a hiring event (which is almost everyone nowadays) the highest that they can bring you in at is GG-10 step 3 (GG is the same scale as GS), so look on the OPM website to see what that pay is. No matter how qualified you are, you must start at grade 10 or lower, so if you are further along in your career, you'll be taking a pay cut not commiserate with how cool you might think it is to work here. Next, promotions only happen once a year and it's an extremely bureaucratic process. Some other agencies will promote lower grade employees (grades 7-9) every six months or so, but not here. Other agencies promote employees automatically every year until grade 13, but not here. At DIA most employees will be able to promote pretty easily every year from grades 7 to 11. But getting promoted from grades 11 to 12 and 12 to 13 will be much more difficult and you may even need to spend 2 years in grade 11 and 2 more years in grade 12 before finally getting to 13. In other words, most other agencies will promote you from 10 to 13 in a matter of 3 years, whereas at DIA it will probably take you 5 or more years. In addition to all this, the promotion process is extremely bureaucratic. Your boss has minimal input on whether you get promoted or not--it's really up to how well you can write your "Performance Application Form" (PAF). Writing the PAF will take you 40+ hours to perfect, then will be reviewed by a promotion panel. The panel's job is to decide who's best qualified for promotion based on how well you articulated your accomplishments on your PAF--not how well you actually performed in your job. So if you have trouble writing resumes, cover letters, etc, you will certainly have difficulties writing the PAF. They do this to keep save money on employee salaries, but in the end it just causes a ton of turn-over in higher grade levels. In the past year, we've had a complete turnover in senior intelligence analysts and section chiefs in my branch with a large team of all new analysts. It amounted to the blind leading the blind. In short, if your goal is to get into the IC, I would recommend applying elsewhere. DIA does hire a lot of entry level employees, so if your goal is just to get your clearance, by all means go ahead and do it--then immediately start looking for jobs at other agencies where you can move up quicker.