I'd definitely update the benchmark to test cases that are close to what you're using in your application, just to make sure you get the best result. Include the lc calls, as well, so you can see if they push you to the regex side.

Oh, yeah, if you're going to do other matches as well, be sure to see if you can incorporate them into the regex to let it get even more performance for you.

Regarding your class--I always found it best to take the course with the teachers other students considered "the hardest", as I found I usually learned more from them. And because of their reputation, I'd keep up on the notes & homework. It's amazing how easy a difficult class is if you keep up on the reading and homework.

...roboticus

Update: Added second paragraph.