Honestly, I'm pretty new to robotics and haven't had a chance to mess around with transistors. I was able to find some videos on solenoids and relays and that made it easy for me to get something up and running quickly.
The latency wasn't an issue though. Even on expert mode on TTFATF, I still had to program a delay to time everything up. But that's great to know for future projects if I need a super low-latency solution.