Yeah, I have one fitted and I love it - no issues, no leaks and very stealthy.
Hilo roofs are very marmite on the forum, but the "Hilo experience" is very much dependent on the installer - it's a time-consuming roof to fit, so it needs to be fitted by someone who doesn't cut corners, otherwise you're very likely to get issues.
Do you know/can you find out who installed the roof? Others whose roof was fitted by the same outfit might then be able to give you their feedback.