Pros
I've subbed for both Round Rock ISD and Leander ISD for many months, and I can easily say that the worst day subbing at Leander ISD is better than some of the best days at Round Rock ISD. For the most part, the students are well disciplined and show some interest in doing their work. The teacher's lounges have Keurigs and are usually well stocked, and the administration and faculty are much more helpful and polite than what I have encountered at Round Rock schools. Though it is a bit of a longer drive for me, I much prefer teacher at an LISD campus, every time.
Cons
Haven't encountered many cons. Substitute teaching pay is always low, so that's normal. Students overall have been generally respectful and will listen, ask questions, and do their work in a responsible manner for the most part. For me, the only con is the long drive to get to many of the Leander ISD campuses. Other than extra time on the road, I have enjoyed virtually every class I have had the pleasure of teaching.