Personally, they both make sense to me. I've always seen a slider option but I'm sure it's more work to implement. State could be an easy way to search on a bigger scope.
I feel like you would have to ask yourself how most people use these features: perhaps someone is searching for the city they live in and are willing to commute "30 miles." They certainly wouldn't want to search the entire state of Texas. Is that the major use-case for users of your site? Forgive me if I'm using an incorrect logic here as I have never done user interface testing but this seems like the sort of thing to think about when designing features.
Honestly though I love the simplicity in design of your site, but the way your job-tile elements are created they're just begging to be clicked on to expand them for more detail.
Both your points make sense. Reg distance slider - do you think option to input state can be an alternative? Would that work for you?