Growing up in San Antonio and currently living in Austin, I have researched extensively the options here, and honestly the two best choices are either UT Health Science Center in San Antonio (program takes a year) or Austin Community College (takes two and a half years because they make you get your intermediate cert. first). These schools have high pass ratings on the NREMT and are of course accredited. I wouldn't go to Acadian or any other programs put on by agencies unless you want to work for that specific agency.
Another thing to consider is the city departments themselves, since you expressed interest in being a firefighter. In San Antonio, the EMS and fire departments are not split, meaning you usually have to work as a firefighter for a few years before you can be "promoted" to paramedic (although there are some other EMS agencies like AMR and Acadian that help out the SAFD on 911 calls). In Austin on the other hand, the fire department is separate from EMS, so you don't have to be a firefighter before you can be a paramedic since they aren't related.
I hope this helps and if you have any other questions, feel free to PM me.
