I worked here seven months while in high school and well, it's not the best Sonic, but it's certainly not the worst. The service is usually pretty fast but I know when I worked there the tea containers didn't get thoroughly cleaned unless a reliable carhop closed the night before.
One of the perks is that it's the only one in the state that I've known to have an eat-in diner. Most of the time it's pretty clean but it's best to go in the morning or early afternoon if you're going to eat in.
All in all I wouldn't work there again (or any fast food place) but I don't have a problem picking up lunch or dinner from them.
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