I use Apollo to manage League Racing Events and Sign Ups. It's simple, easy to use, has a really good interface with all the information needed. Even adjusts the race start time for each members time zones.
I checked out the link above to atomcal, and to be honest the website throws far too much information at you without really explaining the basics of what it does. I couldn't see any examples of what the atomcal sign up process would look like on a Discord or exactly what I'm signing up for. I felt like everything I was clicking on was just trying to take my details and add the bot, and that made me wary of browsing any further. I'm sure it's a great feature, but it's not a great sales pitch and has not convinced me to move away from Apollo!
