I just got a MiFi6620L and wondered if it supported dual-band 2.4 & 5 Ghz simultaneously. The manual implies that it can do this - the options listed are: Dual Band (2.4Ghz/5Ghz), 2.4 Ghz only and 5 Ghz only. I do not see these options; the manual also references guest network which I haven't seen in the actual device menu. Page 60 of MiFi6620L manual:

I downloaded the manual for the ac791L Jetpack and it seems to support either dual-band or separate private and guest networks.
My original plan was to get the 791L but the store didn't have them and suggested the 6620L was the 'latest and greatest'....now I'm wondering if I should exchange the 6620L for the ac791L.....
Thanks in advance for any insights regarding these two devices!!