All testing centers follow the same procedures so there is no material difference with the test. However, choosing the right test center matters. The primary factors to consider are whether you want to take it surrounded by familiar faces or strangers, distance from your home, and other miscellaneous info on the surroundings.
The best place to take the SAT is where you feel comfortable -- same goes for the ACT. Consider that if you take it at your local high school, you'll probably see a lot of your friends. Will you be happy to joke around or unload with them? Or will you be stressed out by all the familiar faces? If you'd rather take the test in obscurity than sign up at a small high school that is offering if the test.
The second thing to consider is how far the testing center is from your house. The SAT is early Saturday morning and groggy students don't crush the SAT. We recommend choosing a place close to home so student's can get a few extra minutes of sleep and no spend too much time in the car building up nerves.
Lastly, we recommend considering any other variables. Do the portables in Cypress Bay High School always freeze like Antarctica? Then either bring a sweater or choose a different location. Does Nova High School have some notoriously uncomfortable seating? Hopefully they fixed it by now. The idea is clear: If there is some lurking factor you are aware of either plan ahead or avoid it.
Generally we recommend taking the SAT or ACT at larger schools because they are more comfortable administering the test and there is less likely to be an administrative error. Cypress Bay High School, Western High School, and Nova High School all do a great job.