We use a SonicWALL TZ 210N as our router, firewall, and content filtering/intrusion prevention system. Basically, everything at the boundary between us and the Internet.
Overall, I've been satisfied with the level of security it has provided. However, Internet performance has left something to be desired, both in terms of the raw speeds we are seeing and also in that we see downloads of all types frequently stalling and having to be restarted multiple times.
Reading online, I have found many people who have encountered these issues with SonicWALL's Gateway Anti-Virus, content filtering, and intrusion prevention services. So, as a test, I disabled all of those and, voila, our speeds nearly doubled and no more stalls. But our network is also wide open.
Short of "dump the SonicWALL, buy something else," which is not really an option for us at this moment, does anyone have experience with this problem and suggestions how to get better performance out of this environment?