The truth is that in LA, most of the companies, especially the dozens of IFT ones are pretty much the same. Yes some pay a little more, some have slightly nicer rigs, some have slightly better schedules, and some have more ER transfers. However, in the end, in LA county, you end up being a glorified medical taxi. You can practice your BLS assessments all day, but still not know a thing about paramedic drugs, cardiology, ect. Even worse, you can develop bad habits because most companies put profit and transports above patient care and there is nobody who is making sure you are doing things the right way. We see it time and time again on these boards where IFT company EMTs get in trouble for activating 911 because their company loses the transport. I know because I worked there and as rude as this sounds, that is now it is. I applaud the EMTs there who keep their head up and strive to be professional even though they get treated like crap by everyone from management, to the transport destinations. If you do work for an LA company, like previous posters said, go for one that has at least 5 or so years in business.
If your end goal is a career in EMS/paramedic school then personally, I would try and get hired on in a surrounding area. Riverside, San Bernardino, Ventura, and Kern counties all have EMS systems where the EMTs are not just taxi drivers and for the most part are partnered with a paramedic. I left LA for Central CA (Where despite what my screen name says I am now a paramedic.) and have never looked back. Think of it as an investment in your future. This is one of the few cases in life where I would say the grass is actually greener. If you are willing to move further away, Fresno, Tulare, Madera, and Kings counties also have EMT/Paramedic 911 units and no IFT companies. I really wish I had not spent time working in LA and had gotten into a real EMS system earlier. All working in LA did was put me further behind and get me stuck in a rut. Anyway, I am sure some will disagree, and I realize there are valid points on both sides, but this is my personal opinion from someone who has seen both sides of the coin.