Trying Meetn since since planning to organise a few education webinars and conferences this year. The UI is simple and very easy to navigate. I also like the ability to send special links for different roles (guest, presenter, etc.) However, flow is not that great:

-If a host private message a guest, they will only be indicated by the popup of chat screen but nothing to tell the guest that there is an unread message. I think a simple indicator (like a small bubble with number) at the specified tab can help.
-Meetn relies heavily on the host. If the host get disconnected for some reasons, the webinar will freeze until the host rejoin the meeting. However, upon rejoining (in our case), the presenter screen on the host side showed a blank screen, so the host was not able to see the presenter's slide thereafter. Having one host only is not recommended for Meetn.
-By default, anyone who enters the room will be able to share their screen. If this feature is ON and hundreds of guests are sharing their screen for some reason, it will eat a lot of bandwidth. The good thing is, the host can disable this DURING the webinar.
--However, the biggest issue in Meetn was with the presenter screen. The presenter was having a hard time sharing the slide screen with our guests which was a Powerpoint slides. We noticed that the PPT did not appear when selecting a tab in the sharing screen. It will ONLY appear when the PPT window is active. When the window (for PPT slides) was minimised, the option to screencast the PPT window in Meetn will disappear. So, we had to ask him to keep the window active (not minimised), and then select the window from the sharing screen. This lead to another problem where Meetn will only show the initial slide (first slide) when the PPT file was shared in the SLIDESHOW mode (in Powerpoint). However, as the speaker moved to the next slide, Meetn will stuck at the first slide. In PPT Normal mode, the screencast works but the slide will be small and shown together with the PPT access toolbar. Hence, the user experience was not that great. I had no issue with other files or windows. The workaround for this could be the use of its Widget, but this will require the host to communicate with the presenter every time.
-One more issue is the streaming quality. There were times when the screen looks pixelated although there was only a few in the room - could be network problem from the guest's side. Another reason could be Meetn reserves higher bandwidth to the presenter compared to guests, which is a logical move.

Overall, the trouble with sharing slides disrupt the normal workflow I had when using other tools such as MS teams and Zoom. Uploading the pdf or ppt files into the widget and later had to convert them to images just for the sake of sharing screen on the go is a bit troublesome. It will be great if the host can just click the ppt in the widget and the slides appear on screen and then allow specific guests or a presenter the ability to control the slide. The usual practice is the presenter will always use PPT files to present, rarely they use PDF.

Overall, I really want Meetn to replace Zoom. However, to be a trendsetter for my organisation and other departments, I am not yet confident to promote Meetn. For a Live webinar Meetn did not meet my expectation as a Zoom alternative, yet. It is a good option for an evergreen webinar which plays with pre recorded videos. Good thing is, Rick is someone who always listen to feedback, so I am sure Meetn will come back stronger. But if nothing happens, may need to refund