I am a sidemount instructor. If my neck injury earlier this year had made it so I couldn't teach ever again, and my 16 year old son asked me if he could take up cave diving in sidemount, the only person I would send him to would be Marissa.
Here's why....
Marissa is thorough and thoughtful in her approach to cave diving. She's patient and fun, but also serious about safety. Also, diving is truly a passion for her, it's not just a paycheck. Like me, even when there's no money involved, she's still diving with her friends and students for fun. There's a commitment to excellence in that. Yes, I realize that we don't always along, and with that info, you should trust the validity of this recommendation.